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  • 201.
    LeBozec, Nathalie
    et al.
    RISE - Research Institutes of Sweden (2017-2019), Materials and Production, KIMAB.
    Persson, Daniel
    RISE - Research Institutes of Sweden (2017-2019), Materials and Production, KIMAB.
    Thierry, Dominique
    RISE - Research Institutes of Sweden (2017-2019), Materials and Production, KIMAB.
    Axelsen, Sten B.
    Statoil ASA, Norway.
    Effect of climatic parameters on filiform corrosion of coated aluminum alloys2004In: Corrosion, ISSN 0010-9312, E-ISSN 1938-159X, Vol. 60, no 6, p. 584-593Article in journal (Refereed)
    Abstract [en]

    The effects of temperature, relative humidity, and wet-dry transition on initiation and propagation of filiform, corrosion on coated aluminum alloy 6016 (AA6016 [UNS A96016]) have been studied. Corrosion products formed in the filament were analyzed using Fourier transform infrared (FTIR)- microspectroscopy. The aluminum surfaces were tested in both milled finish and grinded conditions with chromium, phosphate, and titanium-zirconium-based pretreatment. An electrodeposited coat (ED coat) and a full paint system used for automotive applications (ED coat + topcoat) were investigated for the different combinations of mechanical finish, surface pretreatment, and coating system. In the temperature range between 5°C and 50°C, filiform corrosion, or underfilm corrosion in general, increased significantly. The effect of relative humidity and wet-dry cycling, on the other hand, seems to be strongly influenced by parameters like pretreatment, coating system, and temperature. Filiform corrosion was the highest in the range from 75% to 95% relative humidity (RH), and a distinct maximum was observed at 85% RH for some coating systems. However, filiform. corrosion propagated at humidity down to 40% to 50% RH. For specimens with chromate- and phosphate-based surface pretreatments, filiform, corrosion was lower after exposure to tests with wet-dry cycles. The samples with titanium-zirconium-based pretreatments, on the other hand, had a very poor filiform corrosion resistance in the cyclic test compared to exposures at constant relative humidity. © 2004, NACE International.

  • 202.
    LeBozec, Nathalie
    et al.
    RISE - Research Institutes of Sweden (2017-2019), Materials and Production, KIMAB.
    Thierry, Dominique
    RISE - Research Institutes of Sweden (2017-2019), Materials and Production, KIMAB.
    Pelissier, Krystel
    RISE - Research Institutes of Sweden (2017-2019), Materials and Production, KIMAB.
    A new accelerated corrosion test for marine paint systems used for ship's topsides and superstructures2018In: Materials and corrosion - Werkstoffe und Korrosion, ISSN 0947-5117, E-ISSN 1521-4176, Vol. 69, no 4, p. 447-459Article in journal (Refereed)
    Abstract [en]

    Several studies sponsored by the French Naval Authorities have been conducted during the last 10 years aiming to develop more reliable testing conditions than the conventional neutral salt spray test that should not be used for prediction of material performance. A satisfying correlation to atmospheric field exposure on a ship in service was observed using a 6 months cyclic test from the automotive industry (e.g., Volvo STD23-0014) with a deviation inferior to 25% and an acceleration factor of 4. The possibility to shorten the test duration with a target of 3 months without losing correlation to field exposures is investigated in the present study. A design of experiment is used to study key parameters such as NaCl concentration, the mode of salt application and its frequency as well as the temperature. Ten different marine paint systems used for shipbuilding have been selected. The results indicate an enhancement of the aggressiveness of the test when doubling the salt concentration from 1 to 2 wt%, increasing the number of salt spray per week (from 2 to 3), and the temperature from 35 to 45 °C. The data are compared to marine field exposures in tropical and temperate climates. The most reliable testing conditions to field exposure in marine sites of severity from low C5M to CX on steel include cyclic corrosion tests using 2 wt% of NaCl.

  • 203.
    LeBozec, Nathalie
    et al.
    RISE - Research Institutes of Sweden (2017-2019), Materials and Production, KIMAB.
    Thierry, Dominique
    RISE - Research Institutes of Sweden (2017-2019), Materials and Production, KIMAB.
    Persson, Dag
    RISE - Research Institutes of Sweden (2017-2019), Materials and Production, KIMAB.
    Riener, Christian K.
    RISE - Research Institutes of Sweden (2017-2019), Materials and Production, KIMAB.
    Luckeneder, Gerald H.
    RISE - Research Institutes of Sweden (2017-2019), Materials and Production, KIMAB.
    Influence of microstructure of zinc-aluminium-magnesium alloy coated steel on the corrosion behavior in outdoor marine atmosphere2019In: Surface & Coatings Technology, ISSN 0257-8972, E-ISSN 1879-3347, Vol. 374, p. 897-909Article in journal (Refereed)
    Abstract [en]

    Model hot-dip Zn-Al-Mg coatings with various microstructures were produced in a galvanising simulator by changing the cooling rate. Full characterization of the coatings was performed to identify the chemical composition of the different phases, the size of the grains and their distribution. The corrosion properties of the model microstructures were investigated in outdoor marine atmosphere up to 2 years. Weight loss measurements and cross section observations revealed a tendency for fine microstructures enriched in eutectic phases to be the most corrosion resistant. This was connected to a lower size of cathodic areas at the surface (zinc dendrites), the preferential dissolution of Mg-rich phase (eutectic) and the formation of a stable layered double hydroxide on the surface.

  • 204.
    LeBozec, Nathalie
    et al.
    RISE - Research Institutes of Sweden (2017-2019), Materials and Production, KIMAB.
    Thierry, Dominique
    RISE - Research Institutes of Sweden (2017-2019), Materials and Production, KIMAB.
    Persson, Dan
    RISE - Research Institutes of Sweden (2017-2019), Materials and Production, KIMAB.
    Stoulil, J.
    VSCHT, Czech Republic.
    Atmospheric corrosion of zinc-aluminum alloyed coated steel in depleted carbon dioxide environments2018In: Journal of the Electrochemical Society, ISSN 0013-4651, E-ISSN 1945-7111, Vol. 165, no 7, p. C343-C353Article in journal (Refereed)
    Abstract [en]

    NaCl induced corrosion of Zn-0.2Al, Zn-5Al and Zn-55Al coated steel was investigated at low and ambient CO2 levels.Weight loss measurements revealed an enhancement of the corrosion of Zn-0.2Al and particularly Zn-5Al in low CO2. This was connected to an increase of surface pH in a low CO2 atmosphere promoting the formation of ZnO and layered double hydroxide for Zn-5Al. For Zn-55Al, CO2 depletion did not affect the surface pH due to the acidification effect of Al3+. Preferential dissolution of zinc rich phase was observed on cross-sections, particularly in depleted CO2 experiments. Different sequences of corrosion product formation were proposed for the different Zn-Al coatings. © The Author(s) 2018. Published by ECS. This is an open access article distributed under the terms of the Creative Commons Attribution 4.0 License (CC BY, http://creativecommons.org/licenses/by/4.0/),

  • 205.
    LeBozec, Nathalie
    et al.
    RISE - Research Institutes of Sweden (2017-2019), Materials and Production, KIMAB.
    Thierry, Dominique
    RISE - Research Institutes of Sweden (2017-2019), Materials and Production, KIMAB.
    Rohwerder, Michael
    Max-Planck-Institut für Eisenforschung GmbH,Germany.
    Persson, Dan
    RISE - Research Institutes of Sweden (2017-2019), Materials and Production, KIMAB.
    Luckeneder, Gerald
    Voestalpine, Austria.
    Luxem, Linda
    Thyssen Krupp Steel Europe, Germany.
    Effect of carbon dioxide on the atmospheric corrosion of Zn-Mg-Al coated steel2013In: Corrosion Science, ISSN 0010-938X, E-ISSN 1879-0496, Vol. 74, p. 379-386Article in journal (Refereed)
    Abstract [en]

    The atmospheric corrosion of line hot dip ZnMgAl coating was investigated at low and ambient concentration of CO2 as a function surface chloride concentration and temperature and compared to conventional hot dip galvanised (GI) and Galfan coatings. The corrosion of zinc coatings was enhanced in low CO2 conditions and ZnMgAl material was more affected than GI, and in the range of the Galfan coating. An obvious pH effect was underlined in low CO2 conditions. Layered double hydroxide (LDH) and simonkolleite were mainly formed on ZnMgAl coating in the absence of CO2 while hydroxycarbonate and simonkolleite were dominating in ambient air.

  • 206.
    Leijon, Gunnar
    et al.
    RISE - Research Institutes of Sweden, Materials and Production, KIMAB.
    Ahlström, Johan
    RISE - Research Institutes of Sweden, Materials and Production, KIMAB.
    In-situ hydrogen charging of OFP copper under creep2014Report (Refereed)
    Abstract [en]

    A method to creep test copper intended for nuclear waste disposal during continuous hydrogen charging has been developed and tested. The method has strived to reproduce results published by a Finnish research group. Temperature, stress, strain and other conditions are similar in the two studies. The results show that the method is capable of introducing large amounts of hydrogen into the copper but, in contrast to the Finnish results, no cracks has been observed.

  • 207.
    Leyser, Diego
    et al.
    RISE - Research Institutes of Sweden, Materials and Production, KIMAB.
    Bosch, C.
    Mines Saint-Etienne, France.
    Delafosse, D.
    Mines Saint-Etienne, France.
    Duret-Thual, Claude
    RISE - Research Institutes of Sweden, Materials and Production, KIMAB.
    Querez, Virgine
    RISE - Research Institutes of Sweden, Materials and Production, KIMAB.
    Desamais, N.
    Technip, France.
    Leang, S.
    Technip, France.
    Corrosion-fatigue of carbon steels in sweet and sour corrosion environments: Analysis of cyclic elastic and plastic strain effects on the electrochemical behavior by a transient corrosion current method2017In: NACE - International Corrosion Conference SeriesVolume 5, 2017, Pages 3564-3578Corrosion Conference and Expo 2017; New Orleans; United States; 26 March 2017 through 30 March 2017., National Assoc. of Corrosion Engineers International , 2017, p. 3564-3578Conference paper (Refereed)
    Abstract [en]

    The effects of cyclic stress and strain on corrosion-fatigue in sweet and sour corrosion were studied with an electrochemical approach. Cold-drawn and cold rolled carbon steel samples were mechanically cycled in a confined and CO2-saturated synthetic seawater solution, and their electrochemical response was acquired with a classic 3-electrode apparatus. The effect of elastic static stress was evaluated with the Linear Polarization Resistance (LPR) method. The effect of dynamic stresses, strain rate and plastic strain were evaluated by a potentiostatic method, at imposed steady-state Open Circuit Potential (OCP). Both methods show a linear dependency of the work electrode potential with respect to the applied stress. The latter method allowed the detection of an anodic contribution, proportional to the plastic deformation and to the strain rate. Using these findings, a time-domain model was built, in the form of a RLC circuit, associated to the electrochemical behavior. The calculations show a good agreement with the experimental results, and support the detected influences of stress, strain rate and plastic strain.

  • 208.
    Lindberg, Fredrik
    RISE, Swerea, Swerea KIMAB.
    High resolution electron microscopy study on oxide films formed on nickel-base Alloys X-750, 182 and 82 in simulated high flow velocity BWR water conditions2011In: 15th International Conference on Environmental Degradation of Materials in Nuclear Power Systems-Water Reactors 2011, John Wiley and Sons Inc. , 2011, Vol. 1, p. 357-369Conference paper (Refereed)
    Abstract [en]

    This work contributes to characterization of the oxide films formed on nickel-base alloys (Alloy X-750, Alloy 82 and Alloy 182) under simulated BWR water environments at ∼10 or 18 m/s with or without iron injection. HR SEM/TEM and FIB techniques were applied. The oxide thicknesses on different alloys were substantially different, ranging from 50 nm to 8 μm. For Alloy X-750 and Alloy 182 exposed without iron injection, similar oxide phase compositions consisting of sub-micron Fe2O3 and NiFe 2O4 grains as well as NiO were formed but with substantially different microstructures. For the corroded Alloy X-750 there was an additional dense layer of possibly Ni1.5Cr0.5O 3 in between the NiFe2O4 and NiO layers. On Alloy 82 which contained a relatively low Fe-content only a thin but dense film of Cr1.3Fe0.7O3 was seen. With iron injection the oxide films formed on Alloy 82 were similar to that on the Alloy 182 without iron injection, suggesting that iron injection may play a similar role as if the alloy had an elevated iron content. The implication of the observations for material corrosion behavior in BWRs is elaborated.

  • 209.
    Lindberg, Fredrik
    et al.
    RISE, Swerea, Swerea KIMAB.
    Randelius, Mats
    RISE, Swerea, Swerea KIMAB.
    Jacobsson, Dan
    RISE, Swerea, Swerea KIMAB.
    Komenda, Jacek
    RISE, Swerea, Swerea KIMAB.
    Hagström, Joacim
    RISE, Swerea, Swerea KIMAB.
    Analys av tunna ytskikt med FIB och GDOES2011Report (Refereed)
    Abstract [sv]

    I arbetet med denna rapport undersöktes fokuserad jonstrålemikroskopi (eng. Focused Ion Beam, FIB) för användning vid undersökning av ultratunna ytlager. Metoden jämfördes även med en för oss på KIMAB välkänd teknik, GD-OES (Glow discharge optical emission spectroscopy). Som slutsats kan sägas att metoderna kompletterar varandra bra. Med GD-OES erhålls en analys med god djupupplösning men utan egentlig lateral upplösning (ytan 2-8 mm), den kemiska informationen om skiktets sammansättning är mycket noggrann. FIB är en metod som ger mycket hög lateral upplösning och metoden är mycket väl lämpad för att analysera variationer i skikten. Med FIB fås också detaljerade elektronoptiska bilder med hög upplösning. Nio stycken material studerades i arbetet med rapporten, med fokus på ytlagrets egenskaper, tjocklek och sammansättning.

  • 210.
    Linde, E.
    et al.
    KTH Royal Institute of Technology.
    Blomfeldt, Thomas
    RISE, Swerea, Swerea KIMAB.
    Hedenqvist, M.S.
    KTH Royal Institute of Technology.
    Gedde, U.W.
    KTH Royal Institute of Technology.
    Long-term performance of a DEHP-containing carbon-black-filled NBR membrane2014In: Polymer testing, ISSN 0142-9418, E-ISSN 1873-2348, Vol. 34, p. 25-33Article in journal (Refereed)
    Abstract [en]

    A NBR membrane containing carbon black (36 wt.%) and di(2-ethylhexyl) phthalate (DEHP; 11 wt.%) that had been used at temperatures up to 45 C in pressurised air showed cracking after 2 years in service. Samples were aged in air at elevated temperatures and their mechanical properties were assessed by tensile testing, the glass transition temperature was obtained by DSC, and the DEHP content was determined by liquid chromatography. The loss of DEHP was controlled by the boundary conditions at low temperatures and the loss rate was constant at 90 C within a certain DEHP concentration range (8 to 11 wt.%). The presence of carbon black and DEHP made it impossible to determine oxidation products by infrared spectroscopy. Strain-at-break data were analysed in a way that enabled the effect of DEHP migration to be separated from the effect of thermal oxidation. This allowed extrapolation in both temperature and oxygen pressure domains of high temperature/low oxygen pressure data to the service conditions. The analysis showed that both DEHP evaporation and thermal oxidation had a significant impact on the strain-at-break, but that the latter was the more important. Data for the mechanical properties and the glass transition temperature indicated that oxidation was non-uniform with increasing depth in the specimens. This condition of the 4.5 mm thick samples meant that it was inappropriate to use the specimen Young's modulus for extrapolation purposes. © 2013 Elsevier Ltd. All rights reserved.

  • 211.
    Lindell, David
    RISE - Research Institutes of Sweden (2017-2019), Materials and Production, KIMAB.
    Texture evolution of warm-rolled and annealed 304L and 316L austenitic stainless steels2015In: IOP Conference Series: Materials Science and Engineering / [ed] Skrotzki W.Oertel C.-G., Institute of Physics Publishing , 2015, Vol. 82, article id 012101Conference paper (Refereed)
    Abstract [en]

    The brass-to-copper rolling texture transition is observed during warm rolling austenitic stainless steels. In the current paper austenitic stainless steels 304L and 316L have been subjected to warm rolling at 700°C to 90% reduction. The evolution of microstructure and texture during subsequent annealing has been studied using dilatometry and electron backscatter diffraction. Recrystallisation texture for 304L was primarily cube with some retained rolling texture while 316L only had retained rolling texture. The different behaviour between the two steels is believed to originate from differences in molybdenum content.

  • 212.
    Lindell, David
    et al.
    RISE - Research Institutes of Sweden, Materials and Production, KIMAB.
    Ekman, Thomas
    Aga AB, Sweden.
    Pettersson, Rachel
    Jernkontoret, Sweden.
    Fast and efficient annealing of stainless steel strip using oxyfuel burners2015In: Steel Research International, ISSN 1611-3683, E-ISSN 1869-344X, Vol. 86, no 5, p. 557-566Article in journal (Refereed)
    Abstract [en]

    Pilot plant and annealing experiments have been conducted to study the effect of the higher water content in oxyfuel annealing on oxidation and pickling of cold rolled stainless steel. The experiments were conducted on the austenitic grade AISI 304 in a propane-fired furnace using air and pure oxygen as oxidizers. The experiments were conducted at 1050-1200 °C for typically less than 60 s, in order to simulate industrial annealing of thin strip. Supplementary laboratory annealing trials were made to study the evolution of the microstructure during fast heating rates and short hold times. Increasing the water content from 15 to 50 mol% did not alter the oxidation kinetics or the chemistry of the oxide. Since the oxidation is not altered significantly, the pickling performance of the material remains unchanged. The presence of spalled areas increased the pickling efficiency significantly but this was only seen for material annealed at higher temperature compared to industrial practice. Oxyfuel combustion allows higher heat input and therefore faster heating. The 304 grade recrystallizes readily even at moderate cold rolling reductions so the total annealing time can be reduced substantially if the heating rate can be increased. The present work suggests that this can be done without any downstream effects. Pilot plant annealing experiments have been conducted to study the effect of the higher water content, caused by altering the oxidizer in combustion furnaces, on oxidation and pickling of cold rolled stainless steel. Characterization of oxide, microstructure, mechanical properties, and pickling response suggests that the increasing the water content from 15 to 50 mol% does not result in any negative downstream effects.

  • 213.
    Lindell, David
    et al.
    RISE, Swerea, Swerea KIMAB.
    Pettersson, R.
    Outokumpu Stainless.
    Pickling of process-oxidised austenitic stainless steels in HNO 3-HF mixed acid2010In: Steel Research International, ISSN 1611-3683, E-ISSN 1869-344X, Vol. 81, no 7, p. 542-551Article in journal (Refereed)
    Abstract [en]

    Oxide formation during production annealing and the subsequent pickling response in mixed acid have been studied. The aims were to characterise the oxides formed and to understand how the pickling mechanism and kinetics are affected by the nature of the oxide. Totally, eight different versions of the austenitic stainless steel grades AISI 301, 304L and 309L were studied, all annealed in production lines. Cold rolled oxides (formed during annealing) are thin (< 1 μm), dense and formed in a multilayered manner. Hot rolled oxides (formed during reheating, hot rolling and annealing) are thicker (>1 μm) and more heterogeneous in thickness and composition. The dissolution rate of the chromium depleted layer (CDL) under the oxide is the most important factor for the overall pickling rate. The permeability of acid through the oxide and the tendency of the oxide to spall are also important factors affecting the pickling kinetics. The dense oxide formed on cold rolled materials can to some extent hinder the acid to reach the CDL. The oxides on hot rolled materials are porous and do not provide such a barrier but they are thicker and thereby more difficult to remove. Shot-blasting prior to pickling of the hot rolled materials improves the pickling performance because it thins the oxide, improves the permeability and increases the tendency of the oxide to spall during the pickling step. © 2010 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  • 214.
    Lindell, David
    et al.
    RISE - Research Institutes of Sweden, Materials and Production, KIMAB.
    Pettersson, Rachel
    Jernkontoret, Sweden.
    Crystallographic effects in corrosion of austenitic stainless steel 316L2015In: Materials and corrosion - Werkstoffe und Korrosion, ISSN 0947-5117, E-ISSN 1521-4176, Vol. 66, no 8, p. 727-732Article in journal (Refereed)
    Abstract [en]

    Electron backscatter diffraction and confocal laser microscopy have been used to quantify the degree of crystallographic anisotropy during corrosion of AISI 316L in two test solutions. Corrosion in 30 vol% H2SO4 sulphuric acid shows pronounced crystallographic anisotropy in which the corrosion rate increases in the order {111} < {110} â‰2; {100}. The ratio between the slowest corroding {111} and the fasting corroding {100} surfaces is about 3. Pitting corrosion in a solution of FeCl3 and AlCl3 in ethanol/glycerol agrees with other reported observations that high-atomic density surfaces {111} and {100} are less prone to pit nucleation, however the effect was relative small.

  • 215.
    Linder, Jenny
    RISE, Swerea, Swerea KIMAB.
    Alcoholate corrosion of Aluminium - Influence of water content, surface treatments, temperature, time and pressure2012Report (Refereed)
    Abstract [en]

    As it becomes more important to go from fossil fuels to alternative fuels, biofuels like ethanol are becoming more commercially used. The increased use of ethanol brings good influences such as lower impact on the environment. However, the use of ethanol can also bring negative effects regarding corrosion of metals. In the automotive industry aluminium has been seen affected of a new aggressive corrosion problem, alcoholate corrosion. This study has looked into parameters of alcoholate corrosion; water, temperature, time and pressure. Aluminium alloys AA6063 and A380 have been used and five different surface treatments of AA6063 have been tested to observe if they inhibit the effect of alcoholate corrosion. Throughout the experiments the water dependence of alcoholate corrosion has showed to be of great importance. An increase in water content will postpone the start of alcoholate corrosion or prevent the corrosion to occur. A correlation between temperature and time has been observed. Higher temperatures give a shorter time period of exposure before alcoholate corrosion occurs, and lower temperatures give longer time periods. The effect of different pressures has been studied and shows no effect on alcoholate corrosion when using pressurisation with the inert nitrogen gas. All of the surface treatments have showed to help protect the aluminium alloy against alcoholate corrosion. The electroless nickel plating seems to prevent alcoholate corrosion while Keronite coating seems to be sensitive to this form of corrosion

  • 216.
    Lindgren, Eric
    et al.
    RISE, Swerea, Swerea KIMAB.
    Lundin, Peter
    RISE, Swerea, Swerea KIMAB.
    Fahlström, Karl
    RISE, Swerea, Swerea KIMAB.
    Advanced quality assurance of welded and adhesively bonded joints2014Report (Refereed)
    Abstract [sv]

    Structures and components are often joined steel structures that are heavily subject to fatigue. Common examples of such structures are construction equipment, cranes, bridges, wind towers, trains, ships, vessels, etc. Defects occurring from joining that are hard to identify can cause product failures, this creates enormous demands on the manufacturing process for the probability of detection of defects. To detect defects already in the production with a flexible on-line tool would imply a great competing situation and resource savings. Today quality assurance in production environments is many times performed solely on a few selected areas of the joined structure. Additional destructive evaluation is also commonly used, and in that case around 3-5 cross-sections are randomly selected from a specific part or product, and the geometry is established through macroscopic evaluation and measurements. However, these methods less than 1% of the total joint geometry, and are both time consuming and cost inefficient. Laser induced UltraSonic (LUS) is a contact free ultrasonic technique for non-destructive testing where both generation and detection of the ultrasound is carried out with laser light. The project has evaluated different approaches to measure weld defects that are normally hard to detect including defects in adhesively bonded joints. LUS-measurements were performed on different welded and adhesively bonded structures, with promising results obtained for all evaluated imperfections: - Weld: Internal lack of fusion, cold laps, insufficient penetration - Adhesive: lack of curing, lack of adhesion. Further development of algorithms and analysis is needed to ensure the robustness of the measurement system.

  • 217.
    Lindwall, Greta
    et al.
    RISE, Swerea, Swerea KIMAB.
    Flyg, Jesper
    RISE, Swerea, Swerea KIMAB.
    Frisk, Karin
    RISE, Swerea, Swerea KIMAB.
    Sandberg, O.
    Uddeholms AB.
    Experimental and theoretical investigations of hot isostatically pressed-produced stainless steel/high alloy tool steel compound materials2011In: Metallurgical and Materials Transactions. A, ISSN 1073-5623, E-ISSN 1543-1940, Vol. 42, no 5, p. 1165-Article in journal (Refereed)
    Abstract [en]

    Consolidation of tool steel powders and simultaneous joining to a stainless 316L steel are performed by hot isostatic pressing (HIP). Two tool steel grades are considered: a high vanadium alloyed carbon tool steel, and a high vanadium and chromium alloyed nitrogen tool steel. The boundary layer arising during diffusion bonding is in focus and, in particular, the diffusion of carbon and nitrogen over the joint. Measurements of the elemental concentration profiles and corrosion tests by the double loop-electrochemical potentiokinetic reactivation (DL-EPR) method are performed. Comparative calculations with the DICTRA software are performed and are found to be in agreement with the experimental results. It is found that the carbon tool steel grade has a more critical influence on the corrosion resistance of the stainless 316L steel in comparison to the nitrogen tool steel grade. © 2010 The Minerals, Metals & Materials Society and ASM International.

  • 218.
    Lindwall, Greta
    et al.
    RISE, Swerea, Swerea KIMAB.
    Frisk, Karin
    RISE, Swerea, Swerea KIMAB.
    Assessment and Evaluation of Mobilities for Diffusion in the bcc Cr- Mo-Fe System2011Report (Refereed)
    Abstract [en]

    Assessments of diffusion mobility parameters are performed for diffusion in the bcc Mo-Cr-Fe system by taking available literature data into account. The Mo mobility is in main focus where, in addition to all binaries, ternary interaction parameters are assessed. A diffusion couple is produced and heat treated to cause elemental interdiffusion which is measured experimentally and compared with DICTRA calculations. The obtained experimental information is used for optimization of a mobility parameter. An experiment is also performed in order to study the coarsening of Mo rich M6C carbides embedded in a ferrite matrix, where the diffusion of Mo is believed to be of major importance. The measured coarsening rate is compared with the, by DICTRA, calculated rate showing improved agreement when the assessed kinetic description is applied. We judge the assessment of the bcc Mo- Fe-Cr system to be an important step towards a confident use of kinetic calculations as a tool for development of tool steel materials where Mo diffusion is of importance; for instance, when calculating secondary carbide precipitation during tempering of tool steels.

  • 219.
    Lindwall, Greta
    et al.
    RISE - Research Institutes of Sweden (2017-2019), Materials and Production, KIMAB.
    Frisk, Karin
    RISE - Research Institutes of Sweden (2017-2019), Materials and Production, KIMAB.
    Assessment and evaluation of mobilities for diffusion in the bcc Cr-Mo-Fe system2012In: Journal of Phase Equilibria and Diffusion, ISSN 15477037, Vol. 33, no 5, p. 375-389Article in journal (Refereed)
    Abstract [en]

    An assessment of the diffusion mobility functions for diffusion in the bcc Cr-Fe-Mo system is presented. The optimization of the mobility parameters is performed by utilizing experimental diffusion data available in literature. New diffusion data for the Mo diffusion is produced by a diffusion couple experiment and is accounted for in the optimization. Agreement between calculated and measured diffusion coefficients is found. An M6C coarsening experiment is performed and the measured coarsening rate can be reproduced by diffusion calculation using the DICTRA software and the developed kinetic description. The mobility parameters are shown to have a strong influence on the calculated coarsening rate.

  • 220.
    Lindwall, Greta
    et al.
    RISE, Swerea, Swerea KIMAB.
    Frisk, Karin
    RISE, Swerea, Swerea KIMAB.
    Assessment and evaluation of mobilities for diffusion in the bcc Cr-V-Fe system2009In: Journal of Phase Equilibria and Diffusion, ISSN 15477037, Vol. 30, no 4, p. 323-333Article in journal (Refereed)
    Abstract [en]

    Assessments of diffusion mobility parameters are performed for the bcc Cr-V-Fe alloy system by taking available literature data into account. The main focus is on the diffusion of V in the bcc phase where, in addition to all binaries, ternary interaction parameters are assessed. An experiment is performed in order to study the coarsening of V-rich MC carbide, where the diffusion of V is believed to be of major importance. The measured coarsening rate is compared with the rate calculated using DICTRA, and found to be in satisfactory agreement. The aspects of coarsening experiments as a method to evaluate diffusion mobility data are discussed. © 2009 ASM International.

  • 221.
    Lindwall, Greta
    et al.
    RISE, Swerea, Swerea KIMAB.
    Frisk, Karin
    RISE, Swerea, Swerea KIMAB.
    The effect of nitrogen on the coarsening rate of precipitate phases in iron-based alloys with chromium and vanadium: Experimental and theoretical investigations2013In: International Journal of Materials Research - Zeitschrift für Metallkunde, ISSN 1862-5282, E-ISSN 2195-8556, Vol. 104, no 5, p. 442-451Article in journal (Refereed)
    Abstract [en]

    A comparison of the coarsening of nitrogen-rich vanadium precipitates and the coarsening of carbon-rich vanadium precipitates is presented. The precipitate phases are studied experimentally, via fabrication of model alloys, and theoretically, via simulations utilizing the DICTRA software. The experimental investigations indicate that the nitrogen-rich precipitates exhibit a slower coarsening behaviour than the carbon-rich precipitates. Analysis using thermodynamic and kinetic modelling shows that this can be explained by the higher thermodynamic stability of the nitrogen-rich precipitate compared to the carbon-rich precipitate. The calculated coarsening rates are compared with the measured rates, and found to be in satisfactory agreement using reasonable values for the interfacial energies. The investigations are motivated by the fine precipitate size distribution of nitrides and carbonitrides characteristic for high nitrogen alloyed tool steels produced by means of powder metallurgy. © 2013 Carl Hanser Verlag GmbH &Co. KG.

  • 222.
    Lundholm, Martin
    RISE, Swerea, Swerea KIMAB.
    Mätning av diffusibelt och bundet väte med smältextrationsapparat2014Report (Refereed)
    Abstract [sv]

    I en inledande fas av projektet undersöktes allmänt förutsättningarna att använda en smältextraktionsapparat för mätningar av diffusibelt väte. Två konkreta frågeställningar framkom ur detta. Resterande del av projektet utnyttjades för att utreda och i görligaste mån avhjälpa dessa problem. En standardmetod för att köra diffusibelt och bundet väte i ett prov i en följd utarbetades. När mätningar på bakgrunden från tomma deglar gjordes med denna metod visade det sig att en tydlig topp erhölls vid positionen för det bundna vätet. Detta verkade först underligt eftersom motsvarande varken kunde ses vid positionen för det diffusibla vätet eller för totalvätet då detta mäts med den vanliga metoden. Ett huvudmoment för projektet blev att förklara och minimera denna topp (den s.k. degeltoppen). Den tolkning som framlades och provades var att toppen är väte som gasar ur då effekten under 50s höjs för att driva ut det bundna vätet. Skillnaden mot de andra två fallen är att effekten då länge legat på en konstant nivå som ger en konstant urgasningsnivå. Lämpliga metoder för att minimera och hantera ”degeltoppen” diskuteras sedan. Det andra problem som behandlas i projektet är svårigheterna att med apparaten i fråga göra mätningarna av diffusibelt väte vid en väldefinierad temperatur. Lecos kalibreringsdata går ej under 1400˚C och direkta visuella observationer av emitterat ljus från degeln tyder på att temperaturen ej ens alltid är stabil. Den kvarvarande och tunga delen av projektet ägnades åt att modifiera apparaten och montera en pyrometer för att mäta temperaturen mot degelns sida in situ. En kalibreringsprocedur för att bestämma emissiviteten för degeln utarbetas och med denna känd undersöks temperaturspridningen och temperatur till effekt relationen.

  • 223.
    Lundholm, Martin
    et al.
    RISE, Swerea, Swerea KIMAB.
    Heikkilä, Irma
    RISE, Swerea, Swerea KIMAB.
    Investigation of problems encountered in spectrometic Nitrogen determinations2014Report (Refereed)
    Abstract [sv]

    Seven steel samples previously run by Glow Discharge Spectroscopy were now metallographically investigated by SEM. The aim of the investigation was to see if any features such as cracks, pores or nitrides could be found and correlated to the stability of the GD nitrogen signal. This was indeed the case. The CRM sample JK 2D, previously giving perfect nitrogen stability, had zero measured crack area and the DH 1 (Dillinger Hütte lollipop), being close in stability, only had a very small measured area. All other samples, previously showing scatter above the normal 1 – 1.5 % level, gave appreciably higher crack areas of the order of 0.005%. After the metallographic work the samples were run again spectrometrically to see if the differences in nitrogen scatter between the samples previously established were still the same. This could be verified although the precision ratio for the unstable to stable samples was now reduced from around 4:1 previously to 2:1. It appeared that the special metallographic oxide polishing technique employed for the present investigation caused this reduction although this remains to be verified by continued work. Quite other causes for instabilities and problems were also discussed. It could be shown that certain instabilities on otherwise stable samples were accompanied by high hydrogen signals and it was suggested that the so called H-effect (i.e. the influence of hydrogen on the plasma atomic emission) caused this. It was also shown by calculations how a too limited calibration interval (N ≤ 150 ppm in low-alloyed steel) will amplify the uncertainty of the calibration constants to reach levels far above that of the intensity-scatter of the samples defining them.

  • 224.
    Luo, Chunhui
    et al.
    RISE, Swerea, Swerea KIMAB.
    Siwecki, Tadeusz
    RISE, Swerea, Swerea KIMAB.
    Modelling microstructure evolution during hot rolling of flat and long products of stainless steel2008Conference paper (Refereed)
    Abstract [en]

    Modelling of microstructure evolution during hot rolling of plate and long product of 316L stainless steel has been investigated in the present work. A prediction of microstructure evolution during full scale industrial hot rolling of both plate and bar has been carried out by utilizing the MICDEL model. It has been noted that a correct prediction of strain and strain rate are critical for predicting the recrystallization behaviour of steels during bar rolling. A good relationship has been obtained between the full scale results of austenite grain size predicted by MICDEL and those determined metallographically. © 2008 Verlag Stahleisen GmbH, Düsseldorf.

  • 225.
    Lynch, Peter A
    et al.
    Deakin University, Australia.
    Barnett, Matthew R
    Deakin University, Australia.
    Stevenson, Andrew
    CSIRO Manufacturing, Australia.
    Hutchinson, Bevis
    RISE - Research Institutes of Sweden, Swerea, Swerea KIMAB.
    Characterizing Grain-Oriented Silicon Steel Sheet Using Automated High-Resolution Laue X-ray Diffraction2017In: Metallurgical and Materials Transactions. A, ISSN 1073-5623, E-ISSN 1543-1940, Vol. 48, no 11, p. 5206-10Article in journal (Refereed)
    Abstract [en]

    Controlling texture in grain-oriented (GO) silicon steel sheet is critical for optimization of its magnetization performance. A new automated laboratory system, based on X-ray Laue diffraction, is introduced as a rapid method for large scale grain orientation mapping and texture measurement in these materials. Wide area grain orientation maps are demonstrated for both macroetched and coated GO steel sheets. The large secondary grains contain uniform lattice rotations, the origins of which are discussed.

  • 226.
    Löveborn, D.
    et al.
    RISE - Research Institutes of Sweden, Swerea, Swerea KIMAB.
    Larsson, J. K.
    RISE - Research Institutes of Sweden, Swerea, Swerea KIMAB.
    Persson, K. -A
    RISE - Research Institutes of Sweden, Swerea, Swerea KIMAB.
    Weldability of Aluminium Alloys for Automotive Applications2017In: Physics Procedia, 2017, p. 89-99Conference paper (Refereed)
    Abstract [en]

    Restrictions in CO2-emissions have caused increased demands on decreased weight and increased use of lightweight materials in the automotive industry. Aluminium has shown to be of great interest due to its beneficial weight to strength ratio, and are suitable for hang-on parts such as roof, doors etc. However, the use of aluminium requires reliable joining techniques. This project has been focusing on laser welding of aluminium. It have been reported earlier that hot cracks and porosity are common defects while joining aluminium with laser welding. The aim with this project has been to produce crack free laser welds while joining thin aluminium sheets. Two different optics have been used in this project, oscillating-and triple-spot optics. The results from the experiments show that both the oscillating optics and the triple-spot optics can produce crack free welds. The amount of pores is shown to be low for both cases. The results do also show that the amount of pores in the welds increases with the weld length while the flange length is of minor impact. The mechanical properties are similar for the both optics. The oscillation specimens receive a higher tensile strength while the triple-spot specimens receive a larger elongation at break value. © 2017 The Authors.

  • 227.
    Magnuson, Hans
    et al.
    RISE, Swerea, Swerea KIMAB.
    Frisk, Karin
    RISE, Swerea, Swerea KIMAB.
    Self-diffusion and impurity diffusion of hydrogen, oxygen, sulphur and phosphorus in copper2014Report (Refereed)
    Abstract [sv]

    A study on the mobility of hydrogen, oxygen, sulphur, and phosphorus in copper has been made. In addition, the self-diffusion of copper has also been studied. Literature data has been reviewed, and used to evaluate the temperature expressions of the diffusion coefficients of these elements in copper. The interstitial elements oxygen and hydrogen have been described by a single temperature expression in the whole temperature range, whereas the substitutional elements copper, sulphur, and phosphorus have been modelled according to lattice diffusion at high temperatures and grain boundary diffusion at low temperatures. Sulphur, phosphorus, and copper are believed to be nearly immobile within the crystalline grains at low temperature, even for time periods up to 100 000 years. On the other hand, in the grain boundaries these elements can diffuse a typical distance of 5 cm at the same conditions, determined as an upper limit in diffusion distance. Oxygen is more mobile, and can diffuse 1 mm for 10 000 years. However, since both oxygen and sulphur have a very low solubility any measureable mass transport of these elements will never take place at low temperatures. They will instead form oxides and sulphides in the material. Hydrogen is a mobile element, and will be able to diffuse through 5 cm of copper during a time period of 1000 years at room temperature. The diffusion of hydrogen in copper is experimentally well studied down to room temperature. By combining the evaluated hydrogen diffusion coefficient with the thermodynamically calculated hydrogen content in solid solution the permeability of hydrogen can be explained. This can be used to explain the mass-transport of hydrogen for different times, temperatures, and hydrogen activities (pressures).

  • 228.
    Magnusson, Hans
    RISE - Research Institutes of Sweden (2017-2019), Materials and Production, KIMAB.
    Simulations of internal oxidation and evaluating oxygen mobility in austenite2018In: Euro PM 2018 Congress and Exhibition, European Powder Metallurgy Association (EPMA) , 2018Conference paper (Refereed)
    Abstract [en]

    The process of internal oxidation and reduction of internal oxides is of interest in several powder metallurgy processes. In powder annealing the surface oxides, as well as some internal oxides, are reduced. The reduction of internal oxides depends on the oxygen mobility and the oxide stability at high temperature, which can be simulated by computational tools such as Dictra and Thermo-Calc. Internal oxidation can also occur in other processes, like capsule free HIP or carburisation with minor oxygen content but still enough to cause internal oxidation. Due to the difficulty in evaluating the oxygen mobility by experimental methods one can consider internal oxidation experiments that are the product of both the solubility and diffusivity. This has been done in this work for several different alloying systems; Fe-Cr, Fe-Al, and Fe-Mn. With this approach it is possible to find the most reliable set of thermodynamic and kinetic data to be used in simulations for powder metallurgical processes

  • 229.
    Magnusson, Hans
    et al.
    RISE, Swerea, Swerea KIMAB.
    Frisk, Karin
    RISE, Swerea, Swerea KIMAB.
    An experimental and computational technique suitable for characterisation of oxides2013In: International Powder Metallurgy Congress and Exhibition, Euro PM 2013, European Powder Metallurgy Association (EPMA) , 2013Conference paper (Refereed)
    Abstract [en]

    Understanding of oxide stability is important for processing of sintered steels. The stability of an oxide depends on the alloy composition, temperature and environment for oxidation. The type of oxide and its range of stability can be predicted by thermodynamic calculations. The reactive character of oxygen with metal is a natural difficulty for a thermodynamic study of oxides. In this work, an experimental and computational technique has been developed, allowing for an evaluation of oxide stability. Oxidation results of Fe-Cr-Mn-Si alloys in Ar/H2 atmospheres will be presented, and compared with calculations. Oxidised Fe-6Cr-3Mn-(0-0.1)Si alloys show mainly a spinel oxide with the formula (Fe,Mn)Cr2O4. Silicon is found in separate oxides, rather than combined Cr-Mn-Si oxides. At low partial pressures it appears to be quartz types of oxide SiO2, and at higher partial pressures olivine (Fe,Mn)2SiO4.

  • 230.
    Magnusson, Hans
    et al.
    RISE, Swerea, Swerea KIMAB.
    Frisk, Karin
    RISE, Swerea, Swerea KIMAB.
    Development of an experimental technique suitable for thermodynamic characterisation of oxides2012Report (Refereed)
    Abstract [en]

    The formation of an oxide depends on the alloy composition, temperature of oxidation and oxidation environment defined by its oxygen partial pressure. In aggressive environments a dense oxide layer will be built up (upper figure). In less aggressive environments a matrix with individual oxides will form (lower figure). The type of oxide and its range of stability can be predicted by thermodynamic calculations. An experimental and computational technique has been developed, allowing for a thermodynamic evaluation of oxide stability. Oxidation of Fe-6Cr-3Mn-(0-0.1)Si alloys show mainly a spinel oxide on the formula (Fe,Mn)Cr2O4. Silicon is found in separate oxides, rather than combined Cr-Mn-Si oxides. At low partial pressures it appears to be quartz types of oxide SiO2, and at higher partial pressures it could be olivine (Fe,Mn)2SiO4.

  • 231.
    Magnusson, Hans
    et al.
    RISE - Research Institutes of Sweden, Swerea, Swerea KIMAB.
    Frisk, Karin
    RISE - Research Institutes of Sweden, Swerea, Swerea KIMAB.
    Diffusion, Permeation and Solubility of Hydrogen in Copper2017In: Journal of Phase Equilibria and Diffusion, ISSN 1547-7037, Vol. 38, no 1, p. 65-69Article in journal (Refereed)
    Abstract [en]

    The thermodynamic description for the Cu-H system has been updated. The solubility of hydrogen in copper at low temperature has been backwards calculated from permeability data. The solubility, diffusivity, and permeability of hydrogen in copper can be described by single Arrhenius expressions. These expressions are given below. The temperature dependence of both solubility and diffusivity will together yield a strong temperature dependency on the permeability. The possibility for hydrogen transport in copper is therefore limited at low temperature. (Formula Presented).

  • 232.
    Magnusson, Hans
    et al.
    RISE, Swerea, Swerea KIMAB.
    Frisk, Karin
    RISE, Swerea, Swerea KIMAB.
    Thermodynamic evaluation of the copper-rich part of the CuHOSP system at low temperatures2014In: Calphad, ISSN 0364-5916, E-ISSN 1873-2984, Vol. 47, p. 148-160Article in journal (Refereed)
    Abstract [en]

    A thermodynamic evaluation for CuHOSP has been made, with special focus on the phase stabilities and solubilities for OFP-copper (phosphorus-doped copper). All binary systems including copper have been reviewed. Gaseous species and stoichiometric crystalline phases have been included for higher systems. Calculations for OFP-copper give copper sulphide and copper phosphate as stable phases. No stable hydrogen-rich compound is found stable at atmospheric pressures. Calculations for oxygen-free copper (OF-copper) gives copper oxide instead of copper phosphate. This copper oxide has a lower stability than the copper phosphate, and the copper oxide is more easily reduced by hydrogen forming water vapour. This makes phosphorus an important alloying element for copper alloys in order to minimise the risk of hydrogen embrittlement in copper. © 2014 Elsevier Ltd.

  • 233.
    Markström, Andreas
    et al.
    RISE, Swerea, Swerea KIMAB.
    Andersson, D.
    Royal Institute of Technology.
    Frisk, Karin
    RISE, Swerea, Swerea KIMAB.
    Combined ab-initio and experimental assessment of A1 - x Bx C mixed carbides2008In: Calphad, ISSN 0364-5916, E-ISSN 1873-2984, Vol. 32, no 4, p. 615-623Article in journal (Refereed)
    Abstract [en]

    The excess energies for A1 - x Bx C mixed carbides (where A and B are metals) have been calculated using ab-initio calculations, for 14 systems. A thorough comparison has been made with experimentally assessed excess energies. The comparison shows that conventional ab-initio calculations applied to rather simple structural models can be used to predict the sign, magnitude and symmetry of the excess energy for A1 - x Bx C mixed carbides. The calculated excess energies have also successfully been used to describe several AC-BC systems where the experimental information does not give a unique determination of the excess energy in traditional CALPHAD modelling. The systems that have been studied are CrC-TiC, HfC-NbC, HfC-TaC, HfC-TiC, HfC-VC, NbC-TaC, NbC-VC, NbC-ZrC, TaC-VC, TaC-ZrC, TiC-VC, TiC-ZrC and VC-ZrC. © 2008 Elsevier Ltd. All rights reserved.

  • 234.
    Markström, Andreas
    et al.
    RISE, Swerea, Swerea KIMAB.
    Frisk, Karin
    RISE, Swerea, Swerea KIMAB.
    Experimental and thermodynamic evaluation of the miscibility gaps in MC carbides for the C-Co-Ti-V-W-Zr system2009In: Calphad, ISSN 0364-5916, E-ISSN 1873-2984, Vol. 33, no 3, p. 530-538Article in journal (Refereed)
    Abstract [en]

    Experimental work on the C-Co-Ti-V-W-Zr system in order to determine the extension of the miscibility gaps in TiC-ZrC and VC-ZrC is presented. Thermodynamic calculations were used to design samples that will form a miscibility gap in equilibrium with liquid, WC and graphite. Samples were produced from powder and sintered for 1 week in controlled atmosphere at 1300, 1410 and 1500 {ring operator}C. From the microstructure it could be concluded that the samples form a miscibility gap in equilibrium with liquid, WC and graphite at all temperatures. The composition of the MCx carbides was measured using an analytic SEM. The new experimental information was used to assess the thermodynamic description for the TiC-ZrC system. This work provides valuable information on the miscibility gap in the C-Co-Ti-V-W-Zr system not published previously. © 2009 Elsevier Ltd. All rights reserved.

  • 235.
    Martien, Daffo
    et al.
    RISE - Research Institutes of Sweden (2017-2019), Materials and Production, KIMAB.
    Mendibide, Christophe
    RISE - Research Institutes of Sweden (2017-2019), Materials and Production, KIMAB.
    Duret-Thual, Claude
    RISE - Research Institutes of Sweden (2017-2019), Materials and Production, KIMAB.
    Ferrando, N.
    IFP Energies Nouvelles, France.
    Kittel, J.
    IFP Energies Nouvelles, France.
    Sutter, E.
    Laboratoire Interfaces et Systèmes Electrochimiques, France.
    Tran, T. T. M.
    Laboratoire Interfaces et Systèmes Electrochimiques, France.
    Tribollet, B.
    Laboratoire Interfaces et Systèmes Electrochimiques, France.
    Corrosion of pure iron and hydrogen permeation in the presence of H2S with O2 contamination2018In: NACE - International Corrosion Conference SeriesVolume 2018-April, 2018Corrosion Conference and Expo 2018; Phoenix; United States; 15 April 2018 through 19 April 2018, National Assoc. of Corrosion Engineers International , 2018Conference paper (Refereed)
    Abstract [en]

    This paper examines the influence of traces of oxygen on corrosion and hydrogen charging of steel in an H2S containing environment. It is well known that H2S promotes hydrogen entry into steels, that may result in many types of steel failures such as Hydrogen Induced Cracking (HIC), Sulfide Stress Cracking (SSC), and Stress-Oriented Hydrogen Induced Cracking (SOHIC). Since it is a huge concern for oil and gas industries, standard test methods have been developed and published as NACE technical methods (e.g. NACE TM0284 and NACE TM0177). Though it is recognized that oxygen pollution should be avoided during H2S cracking tests, there is still a lack of experimental data to illustrate the potential impacts of a small oxygen pollution. The aim of the present study is to check if oxygen traces can modify the mechanisms of corrosion and hydrogen charging of steel in H2S containing medium. Experiments consisted of hydrogen permeation measurements through a thin pure iron membrane. They were performed at free potential circuit in order to ensure more realistic environmental conditions. The corrosion rate was also evaluated and test solutions analyzed. 

  • 236.
    Martien, Duffo
    et al.
    RISE - Research Institutes of Sweden (2017-2019), Materials and Production, KIMAB.
    Mendibide, Christophe
    RISE - Research Institutes of Sweden (2017-2019), Materials and Production, KIMAB.
    Duret-Thual, Claude
    RISE - Research Institutes of Sweden (2017-2019), Materials and Production, KIMAB.
    Jean, K.
    IFP Energies Nouvelles, France.
    Ferrando, N.
    IFP Energies Nouvelles, France.
    Sutter, E.
    Laboratoire Interfaces et Systèmes Electrochimiques, France.
    Tran, T. T. M.
    Laboratoire Interfaces et Systèmes Electrochimiques, France.
    Tribollet, B.
    Laboratoire Interfaces et Systèmes Electrochimiques, France.
    EIS study of iron and steel corrosion in aqueous solutions at various concentrations of dissolved H2S: Impact of oxygen contamination2019In: NACE - International Corrosion Conference SeriesVolume 2019-March, 2019, Article number 13041Corrosion Conference and Expo 2019; Nashville; United States; 24 March 2019 through 28 March 2019, National Assoc. of Corrosion Engineers International , 2019Conference paper (Refereed)
    Abstract [en]

    Mildly acidic water containing dissolved H2S presents a strong risk in the cracking of low-carbon steels. Several studies on H2S cracking mechanisms have shown that the main driving force is linked to the ability of H2S to promote hydrogen entry into the bulk material. Standard test methods have been developed and published as NACE technical standards (e.g. NACE TM0284 and NACE TM0177) to aid materials selection in the oil and gas sector. Though it is recognized that oxygen pollution should be avoided during H2S cracking tests, there is a lack of experimental data to illustrate the effects of a small oxygen pollution. Dissolved oxygen concentrations greater than the recommended upper limit (50 parts per billion) can easily be obtained in the case of poor laboratory practices. This paper will focus on the interactions between oxygen and H2S on electrochemical behavior of unalloyed steel. A continuous O2 injection at a level corresponding to 500 ppb is applied, together with H2S bubbling in our test solutions, for periods lasting the same order as SSC standard tests. Steel surface reaction phenomena/corrosion rates in H2S saturated solution, with or without oxygen pollution, are studied using electrochemical impedance spectroscopy. The evolution of corrosion rates obtained from impedance analysis was compared to two other independent methods: i/ weight loss measurements and, ii/ hydrogen permeation. Without O2 pollution, a permeation efficiency of 100% was obtained, as expected. Permeation current density was thus found to match precisely with the corrosion current density determined by impedance analysis at different times. On the other hand, when a continuous O2 pollution was added in the system, significantly higher corrosion rates were observed, associated with test solution acidification. At the same time, permeation efficiency was decreased by up to one order of magnitude. 

  • 237.
    Martien Duvall, Deffo
    et al.
    RISE - Research Institutes of Sweden (2017-2019), Materials and Production, KIMAB.
    Mendibide, Christophe
    RISE - Research Institutes of Sweden (2017-2019), Materials and Production, KIMAB.
    Duret Thual, Claude
    RISE - Research Institutes of Sweden (2017-2019), Materials and Production, KIMAB.
    Sutter, E.
    Laboratoire Interfaces et Systèmes Electrochimiques, France.
    Tran, M.
    Laboratoire Interfaces et Systèmes Electrochimiques, France.
    Tribollet, B.
    Laboratoire Interfaces et Systèmes Electrochimiques, France.
    Ferrando, N.
    IFP Energies nouvelles, France.
    Kittel, J.
    IFP Energies nouvelles, France.
    Impact of oxygen on corrosion and hydrogen permeation of pure iron in the presence of H2S2017In: EUROCORR 2017 - The Annual Congress of the European Federation of Corrosion, 20th International Corrosion Congress and Process Safety Congress 2017, Asociace koroznich inzenyru z.s.- AKI - Czech Association of Corrosion Engineers , 2017Conference paper (Refereed)
    Abstract [en]

    This paper examines the influence of oxygen traces on corrosion and hydrogen charging of steel in H2S containing environment. It is well known that H2S is the driving force for many types of steel failures such as hydrogen induced cracking (HIC), sulfide stress cracking (SSC), and stress-oriented hydrogen induced cracking (SOHIC). Since it is a huge concern for oil and gas industries, standard test methods have been developed and published as NACE technical methods (e.g. NACE TM0284 and NACE TM0177). Though it is recognized that oxygen pollution shall be avoided during H2S cracking tests, there is still a lack of experimental data to illustrate the potential impacts of a small oxygen pollution. The aim of the present study was to check if oxygen traces can modify corrosion mechanisms and hydrogen charging of steel in H2S medium. Experiments consisted in hydrogen permeation measurements through thin pure iron membrane. They were performed at corrosion potential in order to be in realistic environmental conditions. Corrosion rate was also evaluated through weight loss measurements. Analysis of test solutions was performed in order to identify reaction products between H2S and O2

  • 238.
    Martin, David
    et al.
    RISE - Research Institutes of Sweden (2017-2019), Materials and Production, KIMAB.
    Eliasson, Johan
    RISE - Research Institutes of Sweden (2017-2019), Materials and Production, KIMAB.
    Dilatometer analysis of the one step quenching and partitioning process in a 1.5%Si steel2014Conference paper (Refereed)
    Abstract [en]

    A one step quenching and partitioning process was applied to a 0.2%C-2.0%Mn-0.5%Cr- 1.5%Si steel by quenching austenitised samples to several different temperatures below the experimentally determined martensite start temperature of 397 °C and isothermally partitioning them before quenching to room temperature using a quenching deformation dilatometer. These treatments yielded predominantly martensitic microstructures containing 5:6 vol.% to 7:5 vol.% retained austenite, as measured by x-ray diffraction. In each treatment, strong dilation was recorded during isothermal partitioning, with little indication of phase transformation during subsequent cooling to room temperature. This behaviour lends weight to the idea that an isothermal phase transformation occurred during partitioning, and that the final microstructure is a mixture of athermally and isothermally formed constituents. These results also suggest that the final microstructure of this steel is mostly formed before and during partitioning. © (2014) Trans Tech Publications, Switzerland.

  • 239.
    Martin, David
    et al.
    RISE, Swerea, Swerea KIMAB.
    Thoors, Håkan
    RISE, Swerea, Swerea KIMAB.
    Analysis for robust sheet forming processes at high temperatures - Hotform: Analyser för robusta plåtformningsprocesser vid höga temperaturer - Hotform2015Report (Refereed)
    Abstract [en]

    Project vision Building accurate and robust models of the hot forming process requires a detailed understanding of a number of key technical questions pertaining to what is a technologically very complex process, including:  The physical metallurgy, microstructure and properties of modern hot formable steels during and after the hot stamping process  The thermophysical properties (thermal diffusivity, thermal expansion) of modern sheet steels and modern tool materials used in the hot stamping process  The constitutive behavior (strength, work hardenability, anisotropy) of the sheet material during forming  Real temperature-time histories of the formed sheet during hot forming, and heat transfer between sheet and tool  The behavior of the Al-Si coating applied to modern hot formable steels during heating and forming  The role of tool material and surface finish and the influence of different classes of surface coatings on the tribology of the hot forming The answers to these questions can be distilled down into a series of technical parameters and material data which are required for use in finite element simulation. The project aimed to develop methods and conduct experiments which would provide these technical parameters as a way of improving the quality and usefulness of finite element simulation tools for the hot stamping process. The overall goals of the project were  Increase understanding of technical features of the hot forming process  Develop new experimental methods for the analysis of hot forming  Enhance forming simulation accuracy  Shorten lead time for tool production  To maximize the efficiency of the forming tools relative to the cost  Increased productivity of the hot forming process

  • 240.
    Martinsson, Åsa
    et al.
    RISE - Research Institutes of Sweden (2017-2019), Materials and Production, KIMAB.
    Sandström, Rolf
    RISE - Research Institutes of Sweden (2017-2019), Materials and Production, KIMAB. KTH Royal Institute of Technology, Sweden.
    Hydrogen depth profile in phosphorus-doped, oxygen-free copper after cathodic charging2012In: Journal of Materials Science, ISSN 0022-2461, E-ISSN 1573-4803, Vol. 47, no 19, p. 6768-6776Article in journal (Refereed)
    Abstract [en]

    Spent nuclear fuel, in Sweden, is planned to be put in 50-mm thick copper canisters and placed in 500-m depth in the bedrock. Depending on the conditions in the repository, an uptake of hydrogen in the copper may occur. It is therefore necessary to establish how a hydrogen uptake affects the microstructure in both the surface and the bulk. Phosphorus-doped, oxygen-free copper has been cathodically charged with hydrogen for up to 3 weeks. The amount of hydrogen as a function of the distance from the surface was measured by two methods: glow discharge optical emission spectrometry and melt extraction. The penetration of the increased hydrogen content was about 50 μm. Extensive bubble formation took place during the charging. A model has been formulated for the diffusion of hydrogen into the copper, the bubble formation and growth. The model can describe the total amount of hydrogen, the number of bubbles and their sizes as a function of the distance from the surface. Bubbles close to the surface caused the surface to bulge due to the high hydrogen pressure. From the shape of the deformed surface, the maximum hydrogen pressure could be estimated with the help of stress analysis. The maximum pressure was found to be about 400 MPa, which is almost an order of magnitude larger than previously recorded values for electroless deposited copper.

  • 241.
    Martinsson, Åsa
    et al.
    RISE, Swerea, Swerea KIMAB.
    Östling, Henrik
    RISE, Swerea, Swerea KIMAB.
    The effect of cold work on the creep properties of copper2009Conference paper (Refereed)
    Abstract [en]

    Spent nuclear fuel is in Sweden planned to be disposed of by encapsulating in waste packages consisting of a cast iron insert surrounded by a copper canister. The waste package is heavy. Throughout the manufacturing process from the extrusion/pierce-and-draw manufacturing to the final placement in the repository, the copper is subjected to handling which could introduce cold work in the material. It is well known that the creep properties of engineering materials at higher temperatures are affected by cold working. The study includes creep testing of four series of cold worked, oxygen-free, phosphorus doped copper (Cu-OFP) at 75°C. The results are compared to reference series for as-received material carried out in a recent study. Two series of copper cold worked in tension (12 and 24 %) and two series cold worked in compression (12 % parallel to creep load axis and 15 % perpendicular to creep load axis) were tested. The results show that pre-straining in tension of copper leads to prolonged creep life at 75°C. The creep rate and ductility are reduced. The influence on the creep properties increases with the amount of cold work. Cold work in compression applied along the creep load axis has no effect on the creep life or the creep rate. Nonetheless the ductility is still impaired. However, cold work in compression applied perpendicular to the creep load direction has a positive effect on the creep life. Cold work in both tension and compression results in a pronounced reduction of the initial strain on loading. Yet the high value of the area reduction, 90 %, is unaffected by the degree of cold work. © 2009 Materials Research Society.

  • 242.
    Mehanna, M.
    et al.
    CNRS - Université de Toulouse.
    Basseguy, R.
    CNRS - Université de Toulouse.
    Delia, M.-L.
    CNRS - Université de Toulouse.
    Gubner, Rolf
    RISE, Swerea, Swerea KIMAB.
    Sathirachinda, N.
    RISE, Swerea, Swerea KIMAB.
    Bergel, A.
    CNRS - Université de Toulouse.
    Geobacter species enhances pit depth on 304L stainless steel in a medium lacking with electron donor2009In: Electrochemistry communications, ISSN 1388-2481, E-ISSN 1873-1902, Vol. 11, no 7, p. 1476-1481Article in journal (Refereed)
    Abstract [en]

    Geobacter sulfurreducens bacteria increased the open circuit potential of 304L stainless steel by around 320 mV in only a few hours after inoculation. This represents a significant increase in the corrosion risk. In contrast, the oxidation of acetate, which is catalysed by well-established biofilms, shifted the pitting potential towards positive values. In acetate-lacking media, pitting occurred with and without bacteria in the same range of potential values, but the presence of bacteria drastically increased the size of pits. AFM showed pits more than 10 times broader and deeper due to the presence of bacteria. In the absence of acetate, the masking effect due to acetate oxidation disappeared and the full corrosive effect of the biofilm was revealed. This also fully explains why pitting was predominantly observed close to surface areas where bacterial settlement was the densest. © 2009.

  • 243.
    Mei, Nanxuan
    et al.
    KTH Royal Institute of Technology, Sweden.
    Belleville, L.
    KTH Royal Institute of Technology, Sweden.
    Cha, Yingying
    KTH Royal Institute of Technology, Sweden.
    Olofsson, Ulf
    KTH Royal Institute of Technology, Sweden.
    Odnevall Wallinder, Inger Odnevall
    KTH Royal Institute of Technology, Sweden.
    Persson, Kjell Arne
    RISE - Research Institutes of Sweden (2017-2019), Materials and Production, KIMAB.
    Hedberg, Yolanda Susanne
    KTH Royal Institute of Technology, Sweden.
    Size-separated particle fractions of stainless steel welding fume particles – A multi-analytical characterization focusing on surface oxide speciation and release of hexavalent chromium2018In: Journal of Hazardous Materials, ISSN 0304-3894, E-ISSN 1873-3336, Vol. 342, p. 527-535Article in journal (Refereed)
    Abstract [en]

    Welding fume of stainless steels is potentially health hazardous. The aim of this study was to investigate the manganese (Mn) and chromium (Cr) speciation of welding fume particles and their extent of metal release relevant for an inhalation scenario, as a function of particle size, welding method (manual metal arc welding, metal arc welding using an active shielding gas), different electrodes (solid wires and flux-cored wires) and shielding gases, and base alloy (austenitic AISI 304L and duplex stainless steel LDX2101). Metal release investigations were performed in phosphate buffered saline (PBS), pH 7.3, 37°, 24 h. The particles were characterized by means of microscopic, spectroscopic, and electroanalytical methods. Cr was predominantly released from particles of the welding fume when exposed in PBS [3–96% of the total amount of Cr, of which up to 70% as Cr(VI)], followed by Mn, nickel, and iron. Duplex stainless steel welded with a flux-cored wire generated a welding fume that released most Cr(VI). Nano-sized particles released a significantly higher amount of nickel compared with micron-sized particle fractions. The welding fume did not contain any solitary known chromate compounds, but multi-elemental highly oxidized oxide(s) (iron, Cr, and Mn, possibly bismuth and silicon).

  • 244.
    Melander, Arne
    et al.
    RISE - Research Institutes of Sweden (2017-2019), Materials and Production, KIMAB. KTH Royal Institute of Technology, Sweden.
    Delic, Aldin
    RISE - Research Institutes of Sweden (2017-2019), Materials and Production, KIMAB.
    Björkblad, Anders
    RISE - Research Institutes of Sweden (2017-2019), Materials and Production, KIMAB.
    Juntunen, Pasi
    University Oulu, Finland.
    Samek, Ludovic
    Voestalpine Stahl GmbH, Austria.
    Vadillo, Leire
    Tecnalia, Spain.
    Modelling of electro hydraulic free and die forming of sheet steels2013In: International Journal of Material Forming, ISSN 1960-6206, E-ISSN 1960-6214, Vol. 6, no 2, p. 223-231Article in journal (Refereed)
    Abstract [en]

    Electro hydraulic forming of a range of different sheet steels was studied experimentally and with finite element methods. Four carbon and stainless sheet materials were studied. In this paper we present results on a mild steel (IF210), two high strength steels (DPX800 and TRIP700) and one stainless steel (1. 4509). The flow properties of the materials were evaluated at a range of strain rates up to 1000/s. These were typical strain rates in the FE simulations. The flow properties were characterized with the Johnson Cook model. Electro hydraulic forming trails were performed with a chamber of water with a pair of electrodes on one side of the sheet. In one case free forming was performed and in the other case forming was performed into a truncated conical die. Geometrical shapes and strain distributions were evaluated after forming. A finite element model was formulated in ABAQUS explicit. The model takes the chamber filled with water into account and the effect of the electrical discharge is modeled as a pressure wave originating from the location of the electrodes. The sheet is given the properties defined by the Johnson Cook model and stiff tools are used. The forming of the sheet is described including rebound effects at the tools. The model shows satisfactory results in relation to the experimental trials regarding both shape and strains of the pressed sheets.

  • 245.
    Melander, Arne
    et al.
    RISE - Research Institutes of Sweden, Materials and Production, KIMAB. KTH Royal Institute of Technology, Sweden.
    Thoors, Håkan
    RISE - Research Institutes of Sweden, Materials and Production, KIMAB.
    Stenberg, Niclas
    RISE - Research Institutes of Sweden, Materials and Production, KIMAB. KTH Royal Institute of Technology, Sweden.
    Ning, Ma
    RWTH Aachen University, Germany.
    Spring back evaluation for high and ultra high strength sheet steels with the bending under tension machine2015In: International Journal of Material Forming, ISSN 1960-6206, E-ISSN 1960-6214, Vol. 8, no 1, p. 137-144Article in journal (Refereed)
    Abstract [en]

    The Bending Under Tension (BUT) machine is used for evaluation of spring back in sheet metal forming. A strip is drawn over a rotating cylindrical die with different restraining forces. The strip is allowed to spring back after drawing and the curvature of the strip is measured. The loading sequence is typical to wall sections of pressed components, side wall curl, where the material has been bent, unbent and finally unloaded. The test was performed on four high and ultra high strength steels with tensile strengths in the range from 800 MPa to 1300 MPa. A clear separation of the data for the four steels was demonstrated. It was analysed to what extent the differences in spring back between the different steels was related to the differences in tensile strengths. A finite element simulation model was used to simulate the strip curvature after BUT testing. The material parameters of the model were fitted to monotonic uniaxial and equibiaxial tests and uniaxial cyclic tests. The model could describe the experimental data in a satisfactory way.

  • 246.
    Mellin, Pelle
    et al.
    RISE - Research Institutes of Sweden (2017-2019), Materials and Production, KIMAB.
    Björnberg, O.
    SIS Swedish Standards Institute, Sweden.
    Bengtsson, I.
    Bodycote Hot Isostatic Pressing, Sweden.
    Gonzalez, D.
    Bodycote Hot Isostatic Pressing, Sweden.
    Östlund, M.
    Sandvik Materials Technology, Sweden.
    Blom, H.
    Carpenter Powder Products, Sweden.
    Karlsson, J.
    Erasteel Kloster, Sweden.
    Kiamehr, S.
    Uddeholms AB, Sweden.
    A proposed Swedish national standard and best practice for detection of Ar in PM hip material2018In: Euro PM 2018 Congress and Exhibition, European Powder Metallurgy Association (EPMA) , 2018Conference paper (Refereed)
    Abstract [en]

    Ar in metal is present as gaseous voids which affect the material performance; most notably the mechanical properties. In agreement with literature findings, our investigation confirms this for 316L steel produced by PM HIP. Detecting the Ar is possible by microscopy, but more reliably with inert gas fusion followed by gas chromatography or mass spectrometry. The users of these techniques have accumulated experience over the years and consider them robust, especially in terms of distinguishing a presence or absence of Ar. Since consensus has emerged, a standard is now possible. We propose firstly a national standard. It may be used as a quality agreement between the purchaser and provider of the PM HIP service. The proposed standard considers the distinctiveness of PM HIP. For example that Ar tends to segregate in PM HIP cans. In fact, consensus has also been reached on how to reliably sample from PM HIP cans. © European Powder Metallurgy Association (EPMA).

  • 247.
    Mellin, Pelle
    et al.
    RISE, Swerea. KTH Royal Institute of Technology, Sweden.
    Jönsson, Christina
    RISE - Research Institutes of Sweden (2017-2019), Materials and Production, IVF, Energi och miljö. KTH Royal Institute of Technology, Sweden.
    Åkermo, Malin
    KTH Royal Institute of Technology, Sweden.
    Fernberg, Patrik
    RISE, Swerea. Luleå University of Technology, Sweden.
    Nordenberg, Eva
    Siemens Industrial Turbomachinery AB, Sweden.
    Brodin, Håkan
    Siemens Industrial Turbomachinery AB, Sweden.
    Strondl, Annika
    RISE - Research Institutes of Sweden (2017-2019), Materials and Production, KIMAB. KTH Royal Institute of Technology, Sweden.
    Nano-sized by-products from metal 3D printing, composite manufacturing and fabric production2016In: Journal of Cleaner Production, ISSN 0959-6526, E-ISSN 1879-1786, Vol. 139, p. 1224-1233Article in journal (Refereed)
    Abstract [en]

    Recently, the health and environmental perspective of nano-materials has gained attention. Most previous work focused on Engineered Nanoparticles (ENP). This paper examines some recently introduced production routes in terms of generated nano-sized by-products. A discussion on the hazards of emitting such particles and fibers is included. Fine by-products were found in recycled metal powder after 3D printing by Selective Laser Melting (SLM). The process somehow generated small round metal particles (∌1–2 ÎŒm) that are possibly carcinogenic and respirable, but not small enough to enter by skin-absorption. With preventive measures like closed handling and masks, any health related effects can be prevented. The composite manufacturing in particular generated ceramic and carbonaceous particles that are very small and respirable but do not appear to be intrinsically toxic. The smallest features in agglomerates were about 30 nm. Small particles and fibers that were not attached in agglomerates were found in a wide range of sizes, from 1 ÎŒm and upwards. Preventive measures like closed handling and masks are strongly recommended. In contrast, the more traditional production route of fabric production is investigated. Here, brushing residue and recycled wool from fabric production contained few nano-sized by-products.

  • 248.
    Mellin, Pelle
    et al.
    RISE - Research Institutes of Sweden (2017-2019), Materials and Production, KIMAB.
    Lyckfeldt, Ola
    RISE - Research Institutes of Sweden (2017-2019), Materials and Production, IVF.
    Harlin, P.
    AB Sandvik Materials Technology, Sweden.
    Brodin, H.
    Siemens Industrial Turbomachinery AB, Sweden.
    Blom, H.
    Carpenter Powder Products AB, Sweden.
    Strondl, Annika
    RISE - Research Institutes of Sweden (2017-2019), Materials and Production, KIMAB.
    Evaluating flowability of additive manufacturing powders, using the Gustavsson flow meter2017In: Metal Powder Report, ISSN 0026-0657, E-ISSN 1873-4065, Vol. 72, no 5, p. 322-326Article in journal (Refereed)
    Abstract [en]

    The Gustavsson flow meter (including standard ISO-13517) is in this paper used to measure flow rate of fine AM powders. In the current paper, the results are compared to the Hall flow meter and a Freeman FT4 powder rheometer in terms of success of measuring these AM powders. The range of possible powders to measure is smaller with Gustavsson flow meter; but in this range, the difference in flow time is greater compared to the Hall flow meter. Compared to using the rheometer, the Gustavsson flow meter is faster and simpler to use; however, other powder-aspects are evaluated since little correlation was found. For the powders in this paper, all methods of characterizing the flowability could distinguish between (1) two alloys, and (2) if the alloys were new or used (in SLM), and (3) if they were dried or non-dried.

  • 249.
    Mellin, Pelle
    et al.
    RISE - Research Institutes of Sweden (2017-2019), Materials and Production, KIMAB.
    Shvab, Ruslan
    Chalmers University of Technology, Sweden.
    Strondl, Annika
    RISE - Research Institutes of Sweden (2017-2019), Materials and Production, KIMAB.
    Randelius, Mats
    RISE - Research Institutes of Sweden (2017-2019), Materials and Production, KIMAB.
    Brodin, Håkan
    Siemens, Sweden.
    Hryha, Eduard
    Chalmers University of Technology, Sweden.
    Nyborg, Lars
    Chalmers University of Technology, Sweden.
    COPGLOW and XPS investigation of recycled metal powder for selective laser melting2017In: Powder Metallurgy, ISSN 0032-5899, E-ISSN 1743-2901, Vol. 60, no 3, p. 223-231Article in journal (Refereed)
    Abstract [en]

    The purpose of this paper is to compare, in terms of depth composition profile, a recycled hastelloy X powder and a virgin powder of the same alloy. We compare also the COPGLOW (compacted powder glow discharge analysis) method to the more established XPS (X-ray photoelectron spectroscopy) technique, in terms of similarity in reported elemental contents. A good match between the two methods was obtained on the surface of the powder particles (using an etching depth of 1 nm). Similar oxide layer thickness, of about 0.5–1 nm, was found on both powders by COPGLOW. Oxidation sensitive elements, such as Cr, were found on the surfaces by both XPS and COPGLOW on both powders. Surface content of Si appears to have decreased during use in selective laser melting. Finally, the two methods did not otherwise reveal any unexpected features in the depth profiles.

  • 250.
    Mellin, Pelle
    et al.
    RISE - Research Institutes of Sweden (2017-2019), Materials and Production, KIMAB.
    Strand, Emil
    RISE - Research Institutes of Sweden (2017-2019), Materials and Production, KIMAB.
    Heikkilä, Irma
    RISE - Research Institutes of Sweden (2017-2019), Materials and Production, KIMAB.
    Eggertsson, Christer
    RISE - Research Institutes of Sweden (2017-2019), Materials and Production, KIMAB.
    Vang, Jesper
    RISE - Research Institutes of Sweden (2017-2019), Materials and Production, KIMAB.
    Strondl, Annika
    RISE - Research Institutes of Sweden (2017-2019), Materials and Production, KIMAB.
    Incorporating gases (Ar, H2) in PM HIP canisters, using diffusion-filled microspheres2018In: Euro PM 2018 Congress and Exhibition, European Powder Metallurgy Association (EPMA) , 2018Conference paper (Refereed)
    Abstract [en]

    Microspheres are hollow bubbles with a wide range of shell materials available on the market. Gases may enter microspheres via diffusion provided that the temperature is raised. In this paper we used polymeric microspheres to incorporate and control the level of Ar in reference material made by PM HIP, and glass (SiO2) microspheres to incorporate H2 for oxide reduction of PM HIP material. For the incorporation of Ar via polymeric microspheres, we failed to control all factors in the tests with Ar. In spite of that, we can utilize this method to create a homogenous reference material. For the incorporation of H2 via glass (SiO2) microspheres, higher filling pressure is permitted owing to the higher strength of this material. Up to 700 bar filling pressure has been achieved in work aiming for automotive applications. Once the microsphere, after filling, regain room temperature the H2 is locked inside and may be handled safely. We have used this idea to reduce internal and surface oxides on metal powders in the canisters before Hot Isostatic Pressing (HIP), with good results.

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