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  • 1.
    Aronsson Rindby, Anna Cornelia
    et al.
    Chalmers University of Technology.
    Sahlin, Augusta
    Chalmers University of Technology.
    Troell, Eva
    RISE - Research Institutes of Sweden, Swerea, Swerea IVF.
    Kristoffersen, Hans
    RISE - Research Institutes of Sweden, Swerea, Swerea IVF.
    Compilation and validation of heat transfer coefficients of quenching oils2012In: Proceedings of the 6th International Quenching and Control of Distortion Conference Including the 4th International Distortion Engineering Conference, 2012Conference paper (Other academic)
  • 2.
    Belov, Ilia
    et al.
    Jönköping University, Sweden.
    Payandeh, Mustafa
    Jönköping University, Sweden.
    Jarfors, Anders E. W.
    Jönköping University, Sweden.
    Leisner, Peter
    RISE - Research Institutes of Sweden (2017-2019). Jönköping University, Sweden.
    Wessén, Magnus
    Jönköping University, Sweden.
    Effect of fillets on heat transfer in a rheocast aluminium heatsink2016In: 2016 17th International Conference on Thermal, Mechanical and Multi-Physics Simulation and Experiments in Microelectronics and Microsystems (EuroSimE), 2016, article id 7463320Conference paper (Refereed)
    Abstract [en]

    The effect of fillets formed between the base and plate fins of rheocast aluminium heatsinks on the thermal resistance of the heatsinks has been quantified by simulation. Simulation methodology, including sequential optimization has been developed in order to determine hotspot distributions where the fillets have the maximum effect. Combination of different fillet dimensions with various base thickness levels and aluminium alloys having inhomogeneous thermal conductivity have been investigated. For the studied cases, the effect of fillets on heatsink thermal resistance differs from negligible to 6%. The results would guide thermal designers on contribution of fillets to the heat transfer in multi-fin heatsinks for natural convection.

  • 3.
    Berglund, Johan
    et al.
    RISE - Research Institutes of Sweden (2017-2019), Materials and Production, IVF.
    Kjellberg, Mikael
    IUC Olofström, Sweden.
    Liljengren, Magnus
    IUC Olofström, Sweden.
    Kjellsson, Kenneth
    Volvo Cars, Sweden.
    New Test Method for Detection and Analysis of Burrs and Slivers in Trimming and Punching Aluminium Sheet Metal2014Conference paper (Other academic)
    Abstract [en]

     A large problem when trimming or punching aluminium sheet is thecreation of burrs and slivers which degrade the quality of the produced parts. A semiindustrial test for evaluating trimming of aluminium has been further developed toinclude pre-stressing and pre-straining of the sheet material before trimming. Thesemi-industrial test results now show good correlation to industrial productionoutcomes.

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  • 4.
    Bjurenstedt, Anton
    RISE Research Institutes of Sweden, Materials and Production, Manufacturing Processes.
    GRETA – Fallstudie återvunnen aluminium2023Report (Other academic)
    Abstract [en]

    GRETA – a case study on die-cast secondary aluminium

    In ongoing production at AGES in Kulltorp, die-cast components of a secondary aluminium alloy have been continuously taken out for mechanical testing and microstructure investigations. The aim has been to increase the understanding of whether properties vary and, if so, why. In an industrial and well-controlled process, the properties and performance of the obtained material has been analysed for comparison with the original secondary alloy and its specification to see how the material varies during production. The results showed a uniform quality of the produced castings. The hardness test also showed very even results for each component. No statistical difference between the samples could be demonstrated. This means that even if some data collected from the castings were on the edge of the desired range, the properties have not been significantly affected. In other words, there is a higher potential in recycled alloys than that reported in the standard SS-EN 1706:2021. Solidification rate, possible heat treatment and the amount of defects play a decisive role in the final properties of a cast part. By optimizing these, properties that exceed the standard can be obtained.

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  • 5.
    Bjurenstedtare, Anton
    RISE, Swerea, SWECAST.
    Examination of laser treated aluminium2019Report (Other academic)
    Abstract [en]

    The laser treatments of the surfaces have influenced the surface appearance and the microstructure. The effect on the surface appearance is shown in Figure 6. Examination of cross sections revealed a 3-10 μm thick layer of, what appears to be aluminium (based on ocular examination), has formed. The examination in the SEM-EDS gave no answer on the composition of the surface layer formed.

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  • 6.
    Bjurström, Johan
    et al.
    RISE Research Institutes of Sweden, Digital Systems, Smart Hardware. Chalmers University of Technology, Sweden .
    Ohlsson, Fredrik
    RISE Research Institutes of Sweden. Umeå University, Sweden.
    Vikerfors, Andreas
    ReVibe Energy AB, Sweden.
    Rusu, Cristina
    RISE Research Institutes of Sweden, Digital Systems, Smart Hardware.
    Johansson, Christer
    RISE Research Institutes of Sweden, Digital Systems, Smart Hardware.
    Tunable spring balanced magnetic energy harvester for low frequencies and small displacements2022In: Energy Conversion and Management, ISSN 0196-8904, E-ISSN 1879-2227, Vol. 259, article id 115568Article in journal (Refereed)
    Abstract [en]

    In this paper we present a novel concept to efficiently harvest vibrational energy at low frequencies and very small displacement. We describe and evaluate an electromagnetic energy harvester which generates power from a magnetic circuit with motion induced variations of an air gap. External vibrations induce oscillations of the gap length around an equilibrium point, due to a linear spring counteracting the magnetic force. The relative position of the spring can be adjusted to optimize the harvester output for excitation amplitude and frequency. A simulation model is built in COMSOL and verified by comparison with lab measurements. The simulation model is used to determine the potential performance of the proposed concept under both harmonic and non-harmonic excitation. Under harmonic excitation, we achieve a simulated RMS load power of 26.5 μW at 22 Hz and 0.028 g acceleration amplitude. From a set of comparable EH we achieve the highest theoretical power metric of 1712.2 µW/cm3/g2 while maintaining the largest relative bandwidth of 81.8%. Using measured non-harmonic vibration data, with a mean acceleration of 0.039 g, resulted in a mean power of 52 μW. Moreover, the simplicity and robustness of our design makes it a competitive alternative for use in practical situations. © 2022 The Author(s)

  • 7.
    Borgström, Henrik
    RISE Research Institutes of Sweden, Materials and Production, Manufacturing Processes.
    Influence of strain rate, temperature and chemical composition on high silicon ductile iron2021In: Minerals, E-ISSN 2075-163X, Vol. 11, no 4, article id 391Article in journal (Refereed)
    Abstract [en]

    Today, the use of solution hardened ductile iron is limited by brittleness under certain conditions. If chassis components are subjected to loads having high strain rates exceeding those imposed during tensile testing at sub-zero temperatures, unexpected failure can occur. Therefore, it is the purpose of this review to discuss three main mechanisms, which have been related to brittle failure in high silicon irons: intercritical embrittlement, the integrity of the ferritic matrix and deformation mechanisms in the graphite. Intercritical embrittlement is mainly attributed to the formation of Mg-and S-rich grain boundary films. The formation of these films is suppressed if the amount of free Mg-and MgS-rich inclusions is limited by avoiding excess Mg and/or by the passivation of free Mg with P. If the grain boundary film is not suppressed, the high silicon iron has very low elongations in the shakeout temperature regime: 300 to 500◦ C. The integrity and strength of the ferrite are limited by the reduced ordering of the silicumferrite with increasing silicon content, once the “ordinary” ferrite is saturated at 3% silicon, depending on the cooling conditions. Finally, the graphite damaging mechanisms are what dictate the properties most at low temperatures (sub −20◦ C). © 2021 by the author. 

  • 8.
    Borgström, Henrik
    et al.
    RISE - Research Institutes of Sweden (2017-2019), Materials and Production, IVF.
    Hammersberg, Peter
    Chalmers University of Technology, Sweden.
    Hamberg, Kenneth
    Chalmers University of Technology, Sweden.
    Björkegren, Lars-Erik
    LEB Casting Technology, Sweden.
    Lindkvist, Joachim
    Volvo Group, Sweden.
    Modelling the Variation of Tensile Properties of High-Silicon Ductile Iron2018In: One Hundred Twenty-Second Annual Metalcasting Congress, 2018, Vol. 126, p. 155-164, article id art. nr 18-040Conference paper (Refereed)
    Abstract [en]

    For an optimized gating system, the influence of chemical composition can be controlled to a greater extent than in non-optimized conditions, where hidden mechanisms prevail. In this work, GJS-600-10 (EN 1563:2012) solid-solution-strengthened ferritic spheroidal graphite iron with advantageous machinability due to uniform hardness, has been used to elucidate interaction effects and create a material regression model to predict the tensile properties. In this case, key predictors are related to the tensile properties (Rp0,2, Rm, A), of over 120 industrial tensile specimens from 10 years of research. A partial least square (PLS) regression reveals that elements in the steel scrap strongly affect elongation, yield strength and ultimate tensile strength. The analysis reveals that strength to a great extent can be predicted by the chemical composition whereas ductility also depends on other factors.

  • 9.
    Diler, Erwan
    et al.
    RISE Research Institutes of Sweden, Materials and Production, Corrosion.
    Peltier, Fabienne
    RISE Research Institutes of Sweden, Materials and Production, Corrosion.
    Becker, Johan
    RISE Research Institutes of Sweden, Materials and Production, Corrosion.
    Thierry, Dominique
    RISE Research Institutes of Sweden, Materials and Production, Corrosion.
    Real-time corrosion monitoring of aluminium alloys under chloride-contaminated atmospheric conditions2021In: Materials and corrosion - Werkstoffe und Korrosion, ISSN 0947-5117, E-ISSN 1521-4176, Vol. 72, no 8, p. 1377-1387Article in journal (Refereed)
    Abstract [en]

    In this study, the use of electrical resistance (ER) sensors to monitor the corrosion of Al94Cu6 alloy is assessed and compared with 2024-T3 coupons. Under uniform corrosion, a good correlation was found between the ER sensors and mass loss on coupons. Three different chloride depositions are studied: (i) pre-contamination with dry/wet cycles, (ii) Volvo standard accelerated corrosion test and (iii) neutral salt spray test. The obtained results show good reproducibility of the ER sensors under all tested conditions. This suggests that ER sensors more levelled the effect of localised corrosion through a large surface evaluation compared with cross-sections. The corrosion thickness obtained with the ER sensors does not correspond to the mean depth obtained by cross-sections. This can be explained by the distribution and size of the localised corrosion events according to a finite element model proposed. The ER method allows obtaining useful real-time corrosion data for the understanding of the corrosion mechanisms and the development of accelerated tests. The chloride concentration, the frequency of salt application and wet/dry cycles have a strong influence on the corrosion rate of aluminium alloys. © 2021 The Authors. 

  • 10.
    Edström, Adam
    et al.
    RISE - Research Institutes of Sweden (2017-2019), ICT, Acreo.
    Målberg, Sofia
    RISE - Research Institutes of Sweden (2017-2019), ICT, Acreo.
    The Strategic Research Agenda for the Swedish Additive Metal Manufacturing Industry2018Other (Other (popular science, discussion, etc.))
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  • 11.
    Farre, Sten
    RISE Research Institutes of Sweden, Materials and Production, Manufacturing Processes.
    3D-sandprintade kärnor och formar - omvärldsbevakning: del 12021Report (Other academic)
    Abstract [sv]

    En omvärldsbevakning av status för 3D sandprintning (3DSP). beskrivning av tekniken och sammanställning av kända leverantörer av printrar. Tekniken med additiv tillverkning av metalliska material har lett till att utvecklingen av nya komplexa gjutna komponenter har tagit fart. rapport belyser utvecklingen med hjälp av några exempel.

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    3DSP-del 1
  • 12.
    Farre, Sten
    RISE Research Institutes of Sweden, Materials and Production, Manufacturing Processes.
    3D-sandprintningsprocessen: Del 2: Omvärldsanalys, processäkerhet, design, användningsområden.2023Report (Other academic)
    Abstract [sv]

    3D-sandprintning (3DSP) har blivet en del av produktionsapparaten vid framställning av kärnor och formar. rapporten belyser några ekonomiska aspekter och visar på de nya möjligheter som tekniken medför när komplexa gjutna komponenter kan framställas med hjälp av hybrid tekniken även benämt som AM-Cast

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    3DSP-del 2
  • 13.
    Farre, Sten
    RISE Research Institutes of Sweden, Materials and Production, Manufacturing Processes.
    Stålkompetens - från masugn till stålgjutgods2020Report (Other academic)
    Abstract [sv]

    Sverige har alltid hållit sig långt framme när det gäller järn och stålhantering. Kunskaper som har införskaffats inom bruken och senare stålverken har kommit stålgjuterierna till gagn. Rapporten beskriver några områden där kunskap har överförts och ger en överblick av de utmaningar som stålgjuteribranschen står över för. Rapporten är en litteraturstudie där följande frågor har behandlats: Kompentensförsörjning, minskad energiförbrukning, minskning/eliminering av CO2-utsläpp, förändrade materialegenskaper och framtida råvaruresurser.

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    Stålkompetens
  • 14.
    Fredriksson, Stefan
    RISE, Swerea, SWECAST.
    HighT, WP4 – New Technologies2013Report (Other academic)
    Abstract [en]

    This report is a sub project report of a larger project at Swerea SWECAST between 2010 and 2013. The project name is HighT - "Development of High Technology Castings" Within the sub-project the aim was to cast mix materials. In one part of the project, the combination was manganese steel and tool steel. In that part there has been casting trials at Scandinavian Foundry School in Jönköping. In another part of the projet, the combination of different metallic material was white iron and low alloyed steel. In the case with white iron and low alloyed steel a special designed tooth for excavators were designed and cast together with low alloyed steel. The project team is pleased with the results but there are still some questionmarks to straighten out. Hopefully they can be sorted out in a continuation of the project.

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  • 15.
    Gotte, A.
    et al.
    RISE, Swerea, SWECAST.
    Svensson, H.
    RISE, Swerea, SWECAST.
    Seifeddine, S.
    RISE, Swerea, SWECAST.
    Fredriksson, S.
    RISE, Swerea, SWECAST.
    HighT – Development of High Technology Castings2013Report (Other academic)
    Abstract [en]

    Enhanced production and post production techniques and materials optimisation, performed in the project “HighT – Development of High-Technology Castings, have enabled production of cast components with improved mechanical and wear properties as well as lower weight and less variation in properties. Within the project three important fields have been studied; High-Strength Cast Iron, Lightweight Components and Combining materials though casting. The results from the work with High-Strength Cast Iron have enabled production of solution hardened castings with both thin and tick wall sections. By enhanced production of molds and cores, the spread in component properties has also been reduced. Within the work regarding Lightweigt Components, the microstucure and pore content levels have been related to mechanical strength. Also, methods for modelling of residual stresses have been proposed. By combining casting simulation and casting trials, the work related to New Technologies has resulted in an technoque for combining different materials thorugh casting. With this technique, it is possible to produce components with better wear properties than found in today’s wear parts.

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  • 16.
    Gotthardsson, Ulf
    RISE Research Institutes of Sweden, Materials and Production, Manufacturing Processes.
    Jämförelse mellan två kärnbindemedel2023Report (Other academic)
    Abstract [en]

    Comparison between two foundry core binders

    The purpose of this study was to compare the environmental fooprint from two foundry core binders, amine cured Coldbox and SO2 cured epoxy. The study was limited to the process inside the foundry and the main part was about what is generated and emitted from the binders when the cores are used. This was simulated in laboratory trials, where emissions from 150°C in air (simulation of drying refractory coatings) and 600°C (simulation of the actual casting) in oxygen free atmosphere were measured.

    The evaluation was made with parameters used when an Environmental Product Declaration is produced. However, environmental and sustainability data for many substances were missing, which led to that the environmental effects were mainly determined by the amount of binders in the cores.

    In order to receive more general results from this used method, there is a need for better knowledge about the climate effects from the emitted substances.

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  • 17.
    Hearn, William
    et al.
    Chalmers University of Technology, Sweden.
    Cordova, Laura
    Chalmers University of Technology, Sweden.
    Raza, Ahmad
    Chalmers University of Technology, Sweden.
    Dahl-Jendelin, Anton
    RISE Research Institutes of Sweden, Materials and Production.
    Hryha, Eduard
    Chalmers University of Technology, Sweden.
    Impact of powder properties on deoxidation and densification of carbon steels during powder bed fusion – Laser beam2024In: Powder Technology, ISSN 0032-5910, E-ISSN 1873-328X, Vol. 431, article id 119046Article in journal (Refereed)
    Abstract [en]

    This work examined the influence of powder properties on deoxidation and densification of carbon steels during powder bed fusion-laser beam (PBF-LB) at compositions between 0.06 and 1.1 wt% C. Analysis revealed that deoxidation was greatest in alloys with high carbon content, reaching losses of up to 440–600 ppm at compositions of 0.75 and 1.1 wt% C. This behavior was not due to enhanced oxygen removal by spatter, as spatter in high carbon alloys had less oxygen pickup (∼4% vs. ∼27%) and formed smaller oxide layers (∼42 nm vs. ∼82 nm). Instead, it was due to the high oxygen affinity of carbon at elevated temperature, which resulted in formation of gaseous carbon oxides that were subsequently removed by the process atmosphere. Regarding densification, powders with high avalanche energy (>7.75 mJ/kg), break energy (>4.75 mJ/kg), and particle size distribution (D10 > 25 μm) were more likely to form lack of fusion porosity at low energy input.

  • 18.
    Helbert, Varvara
    et al.
    RISE Research Institutes of Sweden, Materials and Production, Corrosion.
    Nazarov, A
    RISE Research Institutes of Sweden, Materials and Production, Corrosion.
    Vucko, Flavien
    RISE Research Institutes of Sweden, Materials and Production, Corrosion.
    Rioual, S.
    Univ Brest, France.
    Thierry, Dominique
    RISE Research Institutes of Sweden, Materials and Production, Corrosion.
    Hydrogen effect on the passivation and crevice corrosion initiation of AISI 304L using Scanning Kelvin Probe2021In: Corrosion Science, ISSN 0010-938X, E-ISSN 1879-0496, Vol. 182, article id 109225Article in journal (Refereed)
    Abstract [en]

    Scanning Kelvin Probe was applied to study passivation of AISI 304L stainless steel after cathodic polarisation. The rate of passivation in air decreased as a function of duration and current density. X-ray Photoelectron Spectroscopy showed enrichment of the surface film by hydroxides of Fe (II) that was the result of hydrogen effusion from the bulk. SKP measured a decreased potential drop in the passive film. Pre-polarisation accelerates the crevice corrosion of steel in presence of chlorides. Using SKP mapping, increased hydrogen sub-surface concentration and lower level of passivity was observed in anodic zones of the crevice.

  • 19.
    Helbert, Varvara
    et al.
    RISE Research Institutes of Sweden, Materials and Production, Corrosion.
    Nazarov, Andrei
    RISE Research Institutes of Sweden, Materials and Production, Corrosion.
    Vucko, Flavien
    RISE Research Institutes of Sweden, Materials and Production, Corrosion.
    Larché, Nicolas
    RISE Research Institutes of Sweden, Materials and Production, Corrosion.
    Thierry, Dominique
    RISE Research Institutes of Sweden, Materials and Production, Corrosion.
    Effect of cathodic polarisation switch-off on the passivity and stability to crevice corrosion of aisi 304l stainless steel2021In: Materials, E-ISSN 1996-1944, Vol. 14, no 11, article id 2921Article in journal (Refereed)
    Abstract [en]

    The effects of cathodic polarisation switch-off on the passivation of AISI 304L stainless steel in air and its crevice corrosion susceptibility in 3.5 wt.% NaCl aqueous electrolyte were investigated. Scanning Kelvin probe (SKP) data showed that the oxide film is significantly destabilised and the rate of steel passivation in air is slowed down. Thermal desorption analysis (TDA) highlighted that hydrogen absorption is proportional to the applied cathodic current density. A special crevice corrosion set-up was designed to realise simultaneous reproducible monitoring of potential and galvanic current to study the impact of prior cathodic polarisation on crevice corrosion onset. © 2021 by the authors.

  • 20.
    Hoier, Philipp
    et al.
    Chalmers University of Technology, Sweden.
    Azarhoushang, Bahman
    Furtwangen University of Applied Sciences, Germany.
    Lundin, Per
    Schlumpf Scandinavia AB, Sweden.
    Malakizadi, Amir
    Chalmers University of Technology, Sweden.
    Badger, Jeffrey
    The Grinding Doc, USA.
    Stormvinter, Albin
    RISE Research Institutes of Sweden, Materials and Production, Manufacturing Processes.
    Björk, Thomas
    Ovako AB, Sweden.
    Klement, Uta
    Chalmers University of Technology, Sweden.
    Hashimoto, Fukuo
    Advanced Finishing Technology Ltd, USA.
    Krajnik, Peter
    Chalmers University of Technology, Sweden.
    Influence of batch-to-batch material variations on grindability of a medium‑carbon steel2022In: Journal of Manufacturing Processes, ISSN 1526-6125, Vol. 73, p. 463-470Article in journal (Refereed)
    Abstract [en]

    This study addresses the influence of material variations on the grindability of crankshaft steel. Most previous studies on the effect of material microstructure on grindability involve comparisons of significantly different steel grades. This study, in contrast, is focused on batch-to-batch grindability variations for one steel grade, a scenario frequently occurring in industry where batches from different steel makers are fed into a production line. For this purpose, a batch made of recycled steel and a batch made of ore-based steel were compared with regards to microstructure and grindability under identical grinding and dressing conditions. Although both batches met the same material specifications, microstructural variations were identified in terms of grain size and micro-constituents (inclusions, carbonitrides). While specific grinding energy, residual stress and full-width at half-maximum profiles of ground surfaces were the same for both batches, the recycled batch showed different and unfavorable variation in wheel wear and Barkhausen noise (BN) response. Larger fractions of oxide inclusions and larger grain sizes (affected by carbonitrides) were present in the recycled batch, which were the likely reasons for the differences in wheel wear and BN response, respectively. These findings may aid grindability improvement by steel-grade adjustments, e.g. modification of the distribution and type of inclusions and/or amount of elements forming carbonitrides. Furthermore, the results highlight the importance of understanding and controlling material microstructure, as existing in-line quality by BN control may not always be able to correctly indicate surface integrity, which could lead to misinterpretations (e.g. false part-rejection on the assumption of grinding burn). © 2021 The Authors

  • 21.
    Holmberg, Jonas
    et al.
    RISE - Research Institutes of Sweden (2017-2019), Materials and Production, IVF.
    Berglund, Johan
    RISE - Research Institutes of Sweden (2017-2019), Materials and Production, IVF.
    Wretland, Anders
    GKN Aerospace Sweden AB, Sweden.
    Beno, Tomas
    University West, Sweden.
    Evaluation of surface integrity after high energy machining with EDM, laser beam machining and abrasive water jet machining of alloy 7182019In: The International Journal of Advanced Manufacturing Technology, ISSN 0268-3768, E-ISSN 1433-3015, Vol. 100, no 5-8, p. 1575-1591Article in journal (Refereed)
    Abstract [en]

    Development of future aero engine components based on new design strategies utilising topological optimisation and additive manufacturing has in the past years become a reality. This allows for designs that involve geometries of “free form” surfaces and material combinations that could be difficult to machine using conventional milling. Hence, alternative manufacturing routes using non-conventional high energy methods are interesting to explore. In this investigation, the three high energy machining methods abrasive water jet machining (AWJM), electrical discharge machining (EDM) and laser beam machining (LBM) have been compared in terms of surface integrity to the reference, a ball nosed end milled surface. The results showed great influence on the surface integrity from the different machining methods. It was concluded that AWJM resulted in the highest quality regarding surface integrity properties with compressive residual stresses in the surface region and a low surface roughness with texture from the abrasive erosion. Further, it was shown that EDM resulted in shallow tensile residual stresses in the surface and an isotropic surface texture with higher surface roughness. However, even though both methods could be considered as possible alternatives to conventional milling they require post processing. The reason is that the surfaces need to be cleaned from either abrasive medium from AWJM or recast layer from EDM. It was further concluded that LBM should not be considered as an alternative in this case due to the deep detrimental impact from the machining process. © 2018, The Author(s).

  • 22.
    Holmberg, Jonas
    et al.
    RISE - Research Institutes of Sweden (2017-2019), Materials and Production, IVF.
    Lundin, Per
    Stresstech OY, Finland.
    Olavisson, Jari
    Volvo Powertrain AB, Sweden.
    Sevim, Solmaz
    Bodycote, Sweden.
    Non destructive testing of surface characteristics after nitrocarburizing of three different steel grades2017Conference paper (Other academic)
  • 23.
    Holmberg, Jonas
    et al.
    RISE - Research Institutes of Sweden (2017-2019), Materials and Production, IVF, Tillverkningsprocesser. University West, Sweden.
    Steuwer, Axel
    Nelson Mandela Metropolitan University, South Africa.
    Stormvinter, Albin
    RISE - Research Institutes of Sweden (2017-2019), Materials and Production, IVF, Tillverkningsprocesser.
    Kristoffersen, Hans
    RISE - Research Institutes of Sweden (2017-2019), Materials and Production, IVF, Tillverkningsprocesser.
    Haakanen, Marja
    Stresstech OY, Finland.
    Berglund, Johan
    RISE - Research Institutes of Sweden (2017-2019), Materials and Production, IVF, Tillverkningsprocesser.
    Residual stress state in an induction hardened steel bar determined by synchrotron- and neutron diffraction compared to results from lab-XRD2016In: Materials Science & Engineering: A, ISSN 0921-5093, E-ISSN 1873-4936, Vol. 667, p. 199-207Article in journal (Refereed)
    Abstract [en]

    Induction hardening is a relatively rapid heat treatment method to increase mechanical properties of steel components. However, results from FE-simulation of the induction hardening process show that a tensile stress peak will build up in the transition zone in order to balance the high compressive stresses close to the surface. This tensile stress peak is located in the transition zone between the hardened zone and the core material. The main objective with this investigation has been to non-destructively validate the residual stress state throughout an induction hardened component. Thereby, allowing to experimentally confirming the existence and magnitude of the tensile stress peak arising from rapid heat treatment. For this purpose a cylindrical steel bar of grade C45 was induction hardened and characterised regarding the microstructure, hardness, hardening depth and residual stresses. This investigation shows that a combined measurement with synchrotron/neutron diffraction is well suited to non-destructively measure the strains through the steel bar of a diameter of 20 mm and thereby making it possible to calculate the residual stress profile. The result verified the high compressive stresses at the surface which rapidly changes to tensile stresses in the transition zone resulting in a large tensile stress peak. Measured stresses by conventional lab-XRD showed however that at depths below 1.5 mm the stresses were lower compared to the synchrotron and neutron data. This is believed to be an effect of stress relaxation from the layer removal. The FE-simulation predicts the depth of the tensile stress peak well but exaggerates the magnitude compared to the measured results by synchrotron/neutron measurements. This is an important knowledge when designing the component and the heat treatment process since this tensile stress peak will have great impact on the mechanical properties of the final component.

  • 24.
    Holmberg, Jonas
    et al.
    RISE - Research Institutes of Sweden (2017-2019), Materials and Production, IVF. University Wes, Sweden.
    Wretland, Anders
    GKN Aerospace Sweden AB, Sweden.
    Berglund, Johan
    RISE - Research Institutes of Sweden (2017-2019), Materials and Production, IVF.
    Grit Blasting for Removal of Recast Layer from EDM Process on Inconel 718 Shaft: An Evaluation of Surface Integrity2016In: Journal of materials engineering and performance (Print), ISSN 1059-9495, E-ISSN 1544-1024, Vol. 25, no 12, p. 5540-5550Article in journal (Refereed)
    Abstract [en]

    The heat generated during EDM melts the work material and thereby allows large amounts to be removed, but an unfavorable surface of a recast layer (RCL) will also be created. This layer has entirely different properties compared to the bulk. Hence, it is of great interest to efficiently remove this layer and to verify that it has been removed. The main objective of this work has been to study the efficiency of grit blasting for removal of RCL on an EDM aero space shaft. Additionally, x-ray fluorescence (XRF) has been evaluated as a nondestructive measurement to determine RCL presence. The results show that the grit-blasting processing parameters have strong influence on the ability to remove RCL and at the same time introduce beneficial compressive stresses even after short exposure time. Longer exposure will remove the RCL from the surface but also increase the risk that a larger amount of the blasting medium will get stuck into the surface. This investigation shows that a short exposure time in combination with a short grit-blasting nozzle distance is the most preferable process setting. It was further found that handheld XRF equipment can be used as a nondestructive measurement in order to evaluate the amount of RCL present on an EDM surface. This was realized by analyzing the residual elements from the EDM wire.

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  • 25.
    Holmberg, Lennart
    et al.
    RISE, Swerea, SWECAST.
    Wänerholm, Martin
    RISE, Swerea, SWECAST.
    Measurement of emissions from iron foundry2013Report (Other academic)
    Abstract [en]

    The highest odour emissions (ouE/h) at iron foundry were measured at the beginning of the cooling line (MP2: FA119) and at the filter of sand reclamtion (MP4: PA8, PA9) and The total odour emissions at iron foundry were 1 748 978 483 ouE/h. The total odour emission in 2012 was 86 305 ouE/h/produced ton.

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  • 26.
    Larché, Nicolas
    et al.
    RISE Research Institutes of Sweden, Materials and Production, Corrosion.
    Emo, Benoit
    Véolia Water, France.
    Allion, Aaudrey
    Aperam Global Research, France.
    Johansson, Elisabeth
    Outokumpu Stainless AB, Sweden.
    Thierry, Dominique
    RISE Research Institutes of Sweden, Materials and Production, Corrosion.
    Localized corrosion of (lean) duplex stainless steels in immersion units of urban wastewater treatment plants2021In: Materials and corrosion - Werkstoffe und Korrosion, ISSN 0947-5117, E-ISSN 1521-4176, Vol. 72, no 8, p. 1338-Article in journal (Refereed)
    Abstract [en]

    With lower alloying cost and higher mechanical properties, lean duplex stainless steels can be an alternative to the more commonly used austenitic stainless steels. However, these alloys are still not the preferred choice, probably due to a lack of field experience. A study was thus initiated in view of defining the limits of use of selected (lean) duplexes for urban wastewater treatment units. The present paper shows the localized corrosion performance of selected lean duplexes in chloride contaminated solutions. The results are compared with austenitic S30403 and S31603 and with the more standard duplexes S82441 and S32205. The effect of welding was also investigated. Exposures in field municipal wastewater plants were conducted for 1 year in low and high chloride content units. The results show that lean duplexes S32101 and S32202 can be used as alternatives to S30403 and S31603 in low chloride electrolytes. At 500 ppm of chloride content, duplex stainless steel S32304 showed better corrosion resistance than S30403 and S31603. For higher chloride contents (1000 ppm and above) the standard duplexes S82441 and S32205 shall be preferred. 

  • 27.
    Larché, Nicolas
    et al.
    RISE Research Institutes of Sweden, Materials and Production, Corrosion.
    Emo, Benoit
    Veolia, France.
    Thierry, Dominique
    RISE Research Institutes of Sweden, Materials and Production, Corrosion.
    Duquesnes, Vincent
    RISE Research Institutes of Sweden, Materials and Production, Corrosion.
    Mendibide, Christophe
    RISE Research Institutes of Sweden, Materials and Production, Corrosion.
    Localized corrosion of lean duplex stainless steels in H2S-containing wet atmosphere from urban wastewater treatment units2021In: Materials and corrosion - Werkstoffe und Korrosion, ISSN 0947-5117, E-ISSN 1521-4176, no 11, p. 1730-Article in journal (Refereed)
    Abstract [en]

    With lower alloying costs and higher mechanical properties, lean duplex stainless steels can be a good alternative to the more commonly used austenitic stainless steels. A study was initiated to define the limits of the use of lean duplex stainless steels for urban wastewater treatment (WWT) units. This paper gives and discusses the corrosion results in an aerated wet atmosphere containing H2S at different levels. Exposures were performed both at laboratory scale and in the field WWT plant for 1 year. A specific probe was also designed to study the corrosion process below water condensate film contaminated with H2S. Under such conditions, the properties of stainless steel were strongly modified with an enhanced risk of localized corrosion. The results obtained on lean duplex materials (UNS S32101, S32202, and S32304) are compared with austenitic UNS S30403 and UNS S31603 and with the more standard duplexes UNS S82441 and UNS S32205. The results show that lean duplexes can be used in aerated wet atmospheres in case of moderate contamination of H2S (<10 ppm) and chloride (<200 ppm). For higher contaminations (e.g., H2S around 100 ppm/chloride around 1000 ppm) the duplex S32205 should be preferred.

  • 28.
    Larché, Nicolas
    et al.
    RISE Research Institutes of Sweden, Materials and Production, Corrosion.
    Leballeur, Charles
    RISE Research Institutes of Sweden, Materials and Production, Corrosion.
    Le Manchet, Sandra
    Industeel-ArcelorMittal, France.
    He, Wenle
    Alleima, Sweden.
    Localized Corrosion of High-Grade Stainless Steels: Grade Selection in Chlorinated Seawater2023In: Corrosion, ISSN 0010-9312, E-ISSN 1938-159X, Vol. 79, no 9, p. 997-1005Article in journal (Refereed)
    Abstract [en]

    Chlorination is widely used in seawater systems to avoid fouling and associated microbial-induced corrosion. Free chlorine is a strong oxidizing agent that prevents biofilm formation on immersed surfaces when used above a certain content. However, the presence of residual chlorine associated with the relatively high chloride content in seawater significantly increases the risk of localized corrosion for most stainless steels. In the present study, a module initially developed to quantify the formation of electroactive biofilms on stainless steels has been used to assess the corrosiveness of chlorinated seawater. Both the electrochemical potential and the cathodic current were measured on super-duplex stainless steel as a function of residual chlorine levels and seawater temperatures. In parallel, long-term localized corrosion tests have been performed in simulated environments to assess the environmental limits for the safe use of high-grade stainless steels in chlorinated seawater. It includes crevice corrosion exposure tests using adapted ISO 18070:2015 crevice formers and internal tube pitting corrosion exposure tests in model tube heat exchangers simulating heat flux from 35°C to 170°C. The synergetic effect of residual chlorine content and temperature on the risk of localized corrosion has been quantified. Corrosion resistance properties are correlated to the electrochemical monitoring data, and the environmental limits of selected base materials stainless steels have been established for duplex stainless steel UNS S32205, super-duplex stainless steel UNS S32750, hyper-duplex stainless steels UNS S32707 and UNS S33207, and the high-grade austenitic stainless steel UNS S31266.

  • 29.
    Lauenstein, Åsa
    RISE - Research Institutes of Sweden (2017-2019), Materials and Production, SWECAST.
    ACDC Test och Demo för hållbara gjutna komponenter2017Report (Other academic)
    Abstract [sv]

    Projektet ACDC syftar till att vidareutveckla Swerea SWECASTs Test- ochdemonstrationsanläggning för utveckling av gjutprocesser och gjutna prototyperoch produkter i riktning mot det övergripande målet att strukturen ska utformas såatt en långsiktig och hållbar drift av anläggningen kan genomföras.T&D-anläggningen är en viktig resurs för forsknings- och uppdragsverksamhetenpå SWECAST. Grunden utgörs av en pågående verksamhet i försöksgjuteriet somtidigare fokuserat på utbildning av gjuterioperatörer och praktiska provgjutningar,men som under en följd av år successivt har breddats till att även inkludera såväldesign- och beredningsprocess som efterkontroll av material och komponenter.Verksamheten inkluderar även en 3D-printer för sandformar och kärnor. På siktär strävan att även inkludera utvärdering av den färdiga komponentens prestandagenom exempelvis utmattningsprovning, korrosionstester och fälttester.Denna delrapport beskriver det arbete som bedrivits under första halvan avprojektet ACDC för att omvandla det tidigare utbildningsjuteriet till en effektivoch funktionell försöksanläggning, hitta nya samverkansformer internt på Swecastsamt ta fram en bärkraftig metodik för framställning av gjutna koncept inomprojekt och uppdrag.Inom projektet ACDC återstår flera viktiga punkter att slutföra under 2017. Enkonkret vision om långsiktig hållbarhet för T&D-anläggningen ska formuleras.Examensarbetet om virtuella modeller ska slutföras och utvärderas. Slutligen ärambitionen att dessutom utforma en modell för Framtidens Gjuteri.

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  • 30.
    Lauenstein, Åsa
    RISE, Swerea, SWECAST.
    Casting of precipitation-hardening steel2014Report (Other academic)
    Abstract [en]

    17-4 PH and its cast equivalent Cb7Cu-1 are stainless precipitation-hardening steels with high strength and good corrosion resistance. Literature shows that the material properties can be tailored in detail by fine-tuning alloy composition and heat treatment. However, the result is also very sensitive to small changes in production environment. The goal of this literature survey has been to define which parameters are essential to make it possible to cast material involving extremely thin sections with d ≤ 1 mm. It has also taken into account the precipitation and hardening mechanisms of the material throughout the different process steps as well as possible means to analyze the resulting material. Additional theoretical calculations have been performed in order to suggest an optimized alloy for subsequent casting trials. The work has been performed within the CLEAN SKY project LEAN: Development of light-weight steel castings for efficient aircraft engines.

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  • 31.
    Liew, YanHan
    et al.
    National University of Singapore,Singapore; Singapore Institute of Manufacturing Technology, Singapore.
    Örnek, Cem
    Istanbul Technical University, Turkey.
    Pan, Jinshan
    KTH Royal Institute of Technology, Sweden.
    Thierry, Dominique
    RISE Research Institutes of Sweden, Materials and Production, Corrosion.
    Wijesinghe, Sudesh
    National University of Singapore,Singapore; Singapore Institute of Manufacturing Technology, Singapore.
    Blackwood, Daniel
    National University of Singapore,Singapore.
    Towards understanding micro-galvanic activities in localised corrosion of AA2099 aluminium alloy2021In: Electrochimica Acta, ISSN 0013-4686, E-ISSN 1873-3859, Vol. 392, article id 139005Article in journal (Refereed)
    Abstract [en]

    The micro-galvanic interactions between Cu-Fe-Mn-Li-containing aluminides and the alloy matrix of aluminium alloy AA2099 during chloride-induced corrosion were investigated in-situ with real-time monitoring of the local contact potential difference (VCPD) using the scanning Kelvin probe force microscopy (SKPFM) at controlled relative humidities. The aluminides showed noble potentials and were able to ennoble their neighbouring matrix sites when a cluster of aluminides surrounded the matrix. The matrix, hence, adopted a more positive VCPD, towards that of the aluminides. The anode-to-cathode ratio changed throughout the corrosion exposure and was seen to show a dynamic character. Much higher local VCPD activities were recorded during the earliest stages of corrosion, when the Al-Li AA2099 surface was first exposed to high humidities, than in later RH cycles; a phenomenon not seen in other aluminium alloys.

  • 32.
    Linjee, Siwat
    et al.
    Chiang Mai University, Thailand.
    Moonngam, Suphitcha
    Chiang Mai University, Thailand.
    Klomjit, Pitichon
    National Science and Technology Development Agency, Thailand.
    Pålsson, Namurata
    RISE Research Institutes of Sweden, Materials and Production, Corrosion.
    Banjongprasert, Chaiyasit
    Chiang Mai University, Thailand.
    Corrosion behaviour improvement from the ultrafine-grained Al–Zn–In​ alloys in Al–air battery2022In: Energy Reports, E-ISSN 2352-4847, Vol. 8, p. 5117-5128Article in journal (Refereed)
    Abstract [en]

    Corrosion of aluminium anode in alkaline solution is a challenging matter for the development of a long-life aluminium anode in Al–air battery. This research focuses on grain size reduction by equal channel angular pressing (ECAP) of Al, Al–Zn, and Al–Zn–In samples. The average grain size of all samples after ECAP is lower than 1μm. Open circuit potential, potentiodynamic polarisation, electrochemical impedance spectroscopy, and self-corrosion test were carried out to study the effects of alloying elements (Zn, In) and grain size reduction by ECAP on the electrochemical behaviours of aluminium alloy anodes. The results show that alloying element, zinc, can improve the stability of ion dissolution by porous Al2ZnO4 film formation. Indium can activate ion dissolution that causes enhanced electrochemical activities for Al–Zn–In sample. Moreover, increasing grain boundaries through grain size reduction can enhance more negative potential and cause a uniformly corroded surface of Al–Zn–In sample, leading to a longer anode life in alkaline solution. © 2022 The Authors

  • 33.
    Liu, Yan
    et al.
    Simtec Soft Sweden AB, Sweden.
    Adolfsson, Erik
    RISE Research Institutes of Sweden.
    Christoffersson, Örjan
    TurnTime Technologies AB, Sweden.
    Hosseini, Seyed B.
    RISE Research Institutes of Sweden, Materials and Production, Manufacturing Processes. TurnTime Technologies AB, Sweden.
    Yan, Zhenghua
    Simtec Soft Sweden AB, Sweden.
    Simulation and Additive Manufacturing of Complexly Designed Aircraft Component2023In: Euro PM2023 Proceedings, European Powder Metallurgy Association (EPMA) , 2023Conference paper (Refereed)
    Abstract [en]

    An innovative component used for the cargo handling systems of Boeing 737 aircraft is developed to improve loaders’ working conditions and protect cargo spaces, passenger luggage, and goods from damage. Since the design of the component makes it difficult to manufacture using conventional techniques, metal Binder Jetting, an Additive Manufacturing technique both faster and more cost-effective compared to the conventional laser/electron beam techniques, is used. However, there is a risk of thermally induced distortion in connection with the post-processing, specifically the sintering step. To address this, a 3D computational fluid dynamics simulation model is developed and simulations are made to identify where and when unwanted distortions may occur during the sintering process. In the simulation, the sintering process follows about 15 hours full sintering cycle with all the heating, holding and cooling stages. The simulations are compared with experiments to validate the numerical results. 

  • 34.
    Lyckfeldt, Ola
    RISE - Research Institutes of Sweden, Swerea, Swerea IVF.
    Metal Powder Characterization for 3D Printing2015In: Proceedings of the 4M International Conference on Multi-Material, 4M/COMM2015, 2015, p. 460-493Conference paper (Other academic)
  • 35.
    Ma, Taoran
    et al.
    RISE Research Institutes of Sweden, Materials and Production, Manufacturing Processes.
    Palmgren, Gustav
    Erasteel Kloster AB, Sweden.
    Jakobsson, Karin
    Erasteel Kloster AB, Sweden.
    Dahl-Jendelin, Anton
    RISE Research Institutes of Sweden, Materials and Production, Manufacturing Processes.
    Vikner, Peter
    Aubert&Duval, France.
    Laser powder bed fusion of hot-work tool steel 1.3397 processed at elevated preheating temperatures2021In: Euro PM2021 Proceedings, 2021Conference paper (Refereed)
    Abstract [en]

    Hot-work tool steel 1.3397 with 0.6 wt% C, 3.9 wt% Cr, 2.0 wt% W and 1.9 % Mo was manufactured by using laser powder bed fusion (LPBF). Early study reported micro-cracks in the as-printed specimens [1], which is a common challenge to additive manufacturing of tool steels containing relatively high carbon. In this work, large cube and bar specimens were produced with the baseplate heated to 400 and 500 ℃ during LPBF to intercept the austenite/martensite transformation and prevent the brittle untempered martensite from forming during LPBF. The as-printed alloy was solution hardened and tempered. It was found that a dendritic/cellular structure with a mixture of untempered martensite and retained austenite was formed. A large number of cracks (~100 μm) were found in the top area of the as-printed 1.3397, due to the shrinkage of the material upon cooling after the printing process. Further approaches to reducing crack are suggested.

  • 36.
    Mölmen, Live
    et al.
    RISE - Research Institutes of Sweden (2017-2019), Safety and Transport, Electronics. Jönköping University, Sweden.
    Braun, Maximilian
    FEM Forschungsinstitut Edelmetalle Metallchemie, Germany.
    Baumgärtner, Manfred
    FEM Forschungsinstitut Edelmetalle Metallchemie, Germany.
    Leisner, Peter
    RISE - Research Institutes of Sweden (2017-2019), Safety and Transport, Electronics. Jönköping University, Sweden.
    Pt-P catalyst for fuel cells2019Conference paper (Other academic)
    Abstract [en]

    Fuel cell technology is becoming increasingly important in a society where the energy system is changing toward a high degree of electrification based on fossil-free primary sources of energy. Among commercial fuel cells, PEM (polymer electrolyte membrane) technology is dominating and the production is doubled each year. The reason for PEM technology being so prosperous is the ability of the industry to manufacture thin film materials (electrodes, membranes and protective films on bipolar plates), while also reaching high current densities. In order to improve the efficiency, catalysts are applied in the electrodes. These improvements have been achieved during the last decades thanks to significant materials development of membranes and electrodes, including micro- and nano-structuring and catalyst development by materials-doping. Thus, PEM technology has a strong potential to offer sustainable, cost effective and flexible solutions.

    However, PEM technology is sensitive to contamination of catalysts and membrane. Additionally, the demanding internal environment (chemistry, temperature, pressure, and dynamic operation make the conditions very harsh) poses complex challenges in terms of durability. Therefore, there are still challenges to overcome to make PEM technology more efficient and robust and thereby beneficial. The most important areas of materials development to reduce the cost of PEM fuel cells are

    • High-performance electrode catalysts enabling ultra-low precious metal loading,
    • Lower cost, lighter, corrosion-resistant bipolar plates,
    • Low cost, high-performance membranes.

    The purpose of the present work is synthesis of catalytic Pt and PtP nanoparticles onto the gas diffusion layer (GDL) of PEM fuel cells by electrodeposition, and in a next step to study aging during fuel cell testing.

    Pt particles with varying P concentration are electrodeposited onto the carbon paper GDL. The concentrations used were 0 at% P, 1 at% P and 10 at% P. The GDL is activated by plasma etching prior to electroplating. The electrolyte used, contained 8 gL-1 Pt as Pt(NO2)2(NH3)2, 70 gL-1  NaCH3COOH and 100 gL-1  Na2CO3. Phosphorous was added in the form of H3PO3. Pulsed electrodeposition was performed at a temperature of 30 °C with an on-time of 0.005 seconds and off-time of 0.195 s. The peak current was 5 A.

  • 37.
    Nagels, Maarten
    et al.
    KU Leuven, Belgium.
    Verhoeven, Brent
    KU Leuven, Belgium.
    Larché, Nicolas
    RISE Research Institutes of Sweden, Materials and Production, Corrosion.
    Dewil, Raf
    KU Leuven, Belgium.
    Rossi, Barbara
    KU Leuven, Belgium; University of Oxford,UK.
    Comparative life cycle cost assessment of (lean) duplex stainless steel in wastewater treatment environments2022In: Journal of Environmental Management, ISSN 0301-4797, E-ISSN 1095-8630, Vol. 306, article id 114375Article in journal (Refereed)
    Abstract [en]

    Some unit operations in wastewater treatment plants (WWTPs), such as settling tanks and pipes for aeration or sludge transfer, are composed of austenitic stainless steel (EN 1.4307 or EN 1.4404) instead of galvanised or painted carbon steel to reduce the maintenance costs. The sensitivity to pitting and crevice corrosion of austenitic grades in certain WWTP environments has also led to the use of duplex grades. The purpose of this study is to evaluate the maintenance of piping systems (WWTPs) and its effect on their life cycle environmental impacts and costs (LCC) for both austenitic and duplex stainless steel grades. The final objective is to aid grade selection for piping in a WWTP environment. The considered functional unit (FU) is a complete piping system. Conventional austenitic stainless steel grades (e.g., EN 1.4404) are studied alongside duplex ones (e.g., EN 1.4362 and EN 1.4462). The calculated environmental impacts are the Global Warming Potential (GWP) and Primary Energy Demand (PED). The production, manufacturing, transport, use including maintenance activities, and end-of-life (burdens and credits) phases are included in the life cycle assessment (LCA). The maintenance activities consist of the required replacements of stainless steel piping during the lifespan of the WWTP. Thus, the service lives of the pipes included in the considered WWTP environment are determined based on long-term corrosion prediction models (power law), which predict the evolution of pit or crevice depth as a function of time. The model parameters are estimated based on own experimental results, supplemented by the existing literature. The corrosion rates determine the number and frequency of replacements, i.e., define the different scenarios of maintenance. The LCA, LCC and corrosion prediction models are then combined into a user-friendly tool, which can be used in industry for an appropriate grade selection for pipes in a WWTP environment. The tool includes several degrees of freedom such as piping distribution, water pressure, chloride content, replacement criteria, etc. The results show that using duplex stainless steel grade EN 1.4462 leads to lower GWP and PED at the end of the WWTP's service life of 40 years. This is mainly due to multiple replacements of the system's parts in wastewater with high levels of chloride (>3000 ppm) if more conventional austenitic stainless steel alloys such as EN 1.4404 are used. Leaner duplex stainless steel grades were also included in this LCC assessment. The duplex grade EN 1.4062 showed the lowest total LCC, thanks to its leaner chemical composition (i.e., lower nickel content) combined with good localized corrosion resistance.

  • 38.
    Neikter, Magnus
    et al.
    University West, Sweden.
    Edin, Emil
    Luleå University of Technology, Sweden.
    Proper, Sebastian
    RISE Research Institutes of Sweden, Materials and Production, Manufacturing Processes.
    Bhaskar, Pahvan
    University West, Sweden.
    Nekkalapudi, Goper
    University West, Sweden.
    Linde, Oscar
    GKN Aerospace Sweden AB, Sweden.
    Hansson, Thomas
    University West, Sweden; GKN Aerospace Sweden AB, Sweden.
    Pederson, Robert
    University West, Sweden.
    Tensile properties of 21-6-9 austenitic stainless steel built using laser powder-bed fusion2021In: Materials, ISSN 1996-1944, E-ISSN 1996-1944, Vol. 14, no 15, article id 4280Article in journal (Refereed)
    Abstract [en]

    Alloy 21-6-9 is an austenitic stainless steel with high strength, thermal stability at high temperatures, and retained toughness at cryogenic temperatures. This type of steel has been used for aerospace applications for decades, using traditional manufacturing processes. However, limited research has been conducted on this alloy manufactured using laser powder-bed fusion (LPBF). Therefore, in this work, a design of experiment (DOE) was performed to obtain optimized process parameters with regard to low porosity. Once the optimized parameters were established, horizontal and vertical blanks were built to investigate the mechanical properties and potential anisotropic behavior. As this alloy is exposed to elevated temperatures in industrial applications, the effect of elevated temperatures (room temperature and 750◦C) on the tensile properties was investigated. In this work, it was shown that alloy 21-6-9 could be built successfully using LPBF, with good properties and a density of 99.7%, having an ultimate tensile strength of 825 MPa, with an elongation of 41%, and without any significant anisotropic behavior. © 2021 by the authors. 

  • 39.
    Odenberger, Eva-Lis
    et al.
    RISE - Research Institutes of Sweden, Materials and Production, IVF. Luleå University of Technology, Sweden.
    Perez Caro, Lluis
    RISE - Research Institutes of Sweden, Materials and Production, IVF. Luleå University of Technology, Sweden.
    Ņhlin, Hans
    Luleå University of Technology, Sweden.
    Oldenburg, Mats
    Luleå University of Technology, Sweden.
    Thermo-mechanical Material Characterization and Stretch-bend Forming of AA60162018In: IOP Conference Series: Materials Science and Engineering, ISSN 1757-8981, E-ISSN 1757-899X, Vol. 418, no 1Article in journal (Refereed)
    Abstract [en]

    Lightweight design has become increasingly in focus for the manufacturing industry. Global environmental challenges, goals and legislations imply that lighter and sustainable products are imperative to remain competitive. One example is stamped products made of aluminum alloys which are of interest to the automotive industry, where lightweight designs are essential. In order to increase formability and to produce more complex geometries in stamped aluminum components there is a need to develop hot forming techniques. The Finite Element Method (FEM) has enabled important advances in the study and design of competitive manufacturing procedures for metal parts. Predicting the final geometry of a component is a complex task, especially if the forming procedure occurs at elevated temperatures. This work presents selected results from thermo-mechanical material testing procedures, FE-analyses and forming validation tests in AA6016 material. The material tests are used to determine the thermo-mechanical anisotropic properties, strain rate sensitivity and formability (Forming Limit Curves, FLC) at temperatures up to 490°C. Stretch-bending tests are performed to compare predicted results with experimental observations such as punch force, strain levels, thinning, forming temperatures, springback and failure. It was found that the heat-treatment and forming at elevated temperatures substantially increased formability and that measured responses could in general be predicted if care was taken to model the initial blank temperatures, heat transfer and thermo-mechanical material properties. The room temperature case confirms the importance of considering anisotropy. © Published under licence by IOP Publishing Ltd.

  • 40.
    Peltier, Fabienne
    et al.
    RISE Research Institutes of Sweden, Materials and Production, Corrosion.
    Thierry, Dominique
    RISE Research Institutes of Sweden, Materials and Production, Corrosion.
    Development of Reliable Accelerated Corrosion Tests for Aluminum Alloys Used in the Aerospace Industry2023In: Corrosion, ISSN 0010-9312, E-ISSN 1938-159X, Vol. 79, no 9, p. 1006-1016Article in journal (Refereed)
    Abstract [en]

    Aluminum alloys are not immune to corrosion which can take the form of localized corrosion. Thus, the assessment of the corrosion behavior of aluminum alloys under atmospheric conditions is a major topic for the aerospace industry. One major difficulty in this task is the lack of robust and reliable accelerated corrosion test(s) in this field. Indeed, several tests as the neutral salt spray test (ASTM B117) are used to assess the general corrosion resistance of aluminum, but these tests were not developed specifically for the aerospace industry and are not representative of service conditions. The aim of the present study was to compare the results of various accelerated corrosion test conditions (ASTM B117, VDA 233-102, Volvo STD 423-0014) with newly developed test conditions. Hence, different accelerated corrosion tests were designed by varying several parameters in the Volvo STD 423-0014 such as the salt concentration, time of wetness, and relative humidity. The results obtained on eight aluminum alloys (2xxx, 7xxx, and Al-Li alloys) were then compared to marine exposures. From the results, one test provides the same type of corrosion attacks on the different alloys under atmospheric exposures in the marine site and a good acceleration factor.

  • 41.
    Peltier, Fabienne
    et al.
    RISE Research Institutes of Sweden, Materials and Production, Corrosion.
    Thierry, Dominique
    RISE Research Institutes of Sweden, Materials and Production, Corrosion.
    Localised corrosion of intermetallic particles on aluminium AA2099-T82021In: Corrosion Engineering, Science and Technology, ISSN 1478-422X, E-ISSN 1743-2782, Vol. 56, no 7, p. 610-Article in journal (Refereed)
    Abstract [en]

    Specimens of AA2099-T8 were immersed for different times ranging from 2 to 180 min in 0.1M NaCl. The development of corrosion around intermetallic particles was studied by scanning electron microscopy (SEM) with energy-dispersive X-ray spectrometry (EDXS). The degradation evolution of each major intermetallic particle after exposure of the alloy to electrolyte allowed to determine which particle corroded during the first stages of immersion. The corrosion of lithium-containing particles was also investigated by transmission electron microscopy (TEM). The earliest stages of attack started with localised corrosion of Al2CuMg (S-phase) particles resulting in dealloying which was followed by trenching around these particles. After 10 min, trenching was observed around Al7Cu2Fe(Mn) particles and then progressed to AlCuFeMnSi particles after 90 min. 

  • 42.
    Pjanic, P.
    et al.
    Ecole Polytechnique Federale de Lausanne, Switzerland.
    Yang, Li
    RISE - Research Institutes of Sweden (2017-2019), Bioeconomy, Papermaking and Packaging.
    Teleman, Anita
    RISE - Research Institutes of Sweden (2017-2019), Bioeconomy, Papermaking and Packaging.
    Hersch, R. D.
    Ecole Polytechnique Federale de Lausanne, Switzerland.
    Angular Color Prediction Model for Anisotropic Halftone Prints on a Metallic Substrate2019In: Journal of Imaging Science and Technology, ISSN 1062-3701, E-ISSN 1943-3522, Vol. 63, no 4, p. 040407-1-040407-11Article in journal (Refereed)
    Abstract [en]

    Under specular reflection, non-isotropic halftones such as line halftones printed on an ink-receiving plastic layer superposed with a metallic layer change their colors upon in-plane rotation of the print. This color change is due to the orientation-dependent optical dot gain of the halftone. A strong dot gain occurs when the incident light is perpendicular to the halftone line structure. A color prediction model is proposed which predicts under specular reflection the color of cyan, magenta and yellow line halftones as a function of the azimuthal rotation angle, the incident angle and the line frequency. The model is calibrated by measuring 17 reflectances at the (25 : 25) measurement geometry, with the incident light parallel to the halftone lines. The model has been tested for several azimuthal rotation and incident viewing angles, each time for 125 different cyan, magenta and yellow ink surface coverages.

  • 43.
    Prestat, Michel
    et al.
    RISE Research Institutes of Sweden, Materials and Production, Corrosion.
    Vucko, Flavien
    RISE Research Institutes of Sweden, Materials and Production, Corrosion.
    Holzer, L.
    Zurich University of Applied Sciences, Switzerland.
    Thierry, Dominique
    RISE Research Institutes of Sweden, Materials and Production, Corrosion.
    Microstructural aspects of Ti6Al4V degradation in H2O2-containing phosphate buffered saline2021In: Corrosion Science, ISSN 0010-938X, E-ISSN 1879-0496, Vol. 190, article id 109640Article in journal (Refereed)
    Abstract [en]

    Ti6Al4V surfaces were exposed to simulated inflammation conditions in H2O2-containing phosphate buffered saline with and without FeCl3. Scanning electron microscopy analysis revealed significantly different degradation modes for the α and β phases. While the α grains are covered by a ca. 400 nm thick protective nanostructured oxide layer, the attack of the β phase generates a porous microstructure with microscaled cracks and a low polarization resistance. The β phase is postulated to be sensitive to H2O2 reduction products and less able to generate a passive oxide film. The presence of FeCl3 enhances the cathodic activity and the β phase degradation.

  • 44.
    Pélissier, Krystel
    et al.
    RISE Research Institutes of Sweden, Materials and Production, Corrosion.
    Thierry, Dominique
    RISE Research Institutes of Sweden, Materials and Production, Corrosion.
    Multiscale and multi-technical approach to characterize the hot-dip galvanized steel surface and its consequence(S) on paint adhesion and tendency to blistering2021In: Coatings, ISSN 2079-6412, Vol. 11, no 6, article id 704Article in journal (Refereed)
    Abstract [en]

    It is well known that the surface state (cleanliness, composition) of galvanized steel prior to the application of an organic coating is an important parameter. The surface state will affect the adhesion properties of the complete system and therefore will also impact its corrosion resistance and its tendency to blistering. Before the application of a pretreatment layer, galvanized steel strips are normally alkaline cleaned. This step is known to remove the native oxide film formed on hot dip galvanized steel after processing and appears as one of the most important steps to study the impact of the surface properties on the performance of painted systems. This study focused on making use of the cleaning step to input a variability on the surface composition (mainly surface concentration of aluminum) and evaluate its consequence(s) on the performance of a complete paint system. The results showed that, a variability in terms of surface aluminum concentration could be achieved by the cleaning step and that signs of performance improvement in terms of adhesion and tendency to blistering were spotted with a low content of aluminum at the surface.

  • 45.
    Risberg, Martin
    et al.
    RISE, Swerea, SWECAST.
    Gotte, Anders
    RISE, Swerea, SWECAST.
    Development of light-weight steel castings for efficient aircraft engines - Summary report2014Report (Other academic)
    Abstract [en]

    This report summaries the work carried out in the project, LEAN - Development of light-weight steel castings for efficient aircraft engines. The overall object in the project was to develop thinner cast steel components for aircraft engines. The work was conducted in collaboration between research institutes and industry. Swerea SWECAST, the Swedish foundry institute, which has a long tradition in collaboration with the industry in research projects, was the project leader and leader in one of the work packages. FRI, the Polish Foundry Research Institute, which has advance equipment for material science and material data investigations, was the leader of the second work package. The investment foundry TPC Components AB conducted casting trials and contributed with their wide knowledge of investment casting. Casting trials have been performed in order to investigate the influence of different process parameters governing the fluidity of thin walled investment castings. The alloy used was CbCu7-1, i.e. the cast analogy of the stainless precipitation-hardening steel 17-4PH. Two levels of geometry complexity were used as well as top- and bottom gated casting systems. In the first trial, a blade thicknesses ranging from 0.7-2.0 mm was used. In the second trial, some features were added to the blade as well as a textured surface on one side. It was shown that the top gated casting system showed an overall improved fluidity compared to the bottom gated casting system for the simpler geometry. Blade thickness and pouring temperature were shown to have the greatest impact on fluidity. Adding some geometrical features to the simple geometry drastically decreased the differences between the filling systems. Using a one side textured blade with thickness of 1.3 and 1.5 mm was comparable with 1.5 and 2.0 mm flat castings thus reducing weight of the thinnest sections of a steel casting. Predictions of miss-runs with simulations were shown to be in good agreement with experiments and gave valuable insight to problems in the casting trials. Differences in porosity levels were seen between the top- and bottom gated casting systems for the simpler geometry at high metal temperatures, where the former showed a larger amount of porosity. Besides the work performed on fluidity of the cast analogy of 17-4PH, a number of other alloys not commonly used for castings today were evaluated in terms of their fluidity and were compared to 17-4PH. The casting trials were performed with a bar casting. It was shown that JETHETE 152M had the best fluidity followed by Custom 465, L0H12N4M and 17-4PH. CSS 42L and PH13-8M ranked worst in the fluidity comparison and were therefore excluded from further investigations. Mechanical testing at both ambient and elevated temperatures (400 degrees Celsius) was performed. It was concluded that JETHETE 152M was the best performing alloy with respect to mechanical properties, followed by L0H12N4M, 17-4PH and Custom 465. However, JETHETE 152M was later excluded due to its poor corrosion properties. In the corrosion test, at 400 degrees Celsius, for 100 hours with salt spray fog, it was determined that the 17-4PH and L0H12N4M showed similar corrosion rates. Wettability test performed on two different shell systems with 17-4PH showed that the shell/alloy system is important to consider during filling of thin sections. The 17-4PH alloy was used in the casting trials of a demonstrator. It was demonstrated during the casting trials that filling of a wide flat section with a thickness below 2 mm is hard to achieve.

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  • 46. Rohde, S. E.
    et al.
    Bennett, A. I.
    Harris, Kathryn L
    University of Florida, USA.
    Ifju, P. G.
    Angelini, T. E.
    Sawyer, W. G.
    Measuring Contact Mechanics Deformations Using DIC through a Transparent Medium2017In: Experimental mechanics, ISSN 0014-4851, E-ISSN 1741-2765, Vol. 57, no 9, p. 1445-1455Article in journal (Refereed)
    Abstract [en]

    This paper describes the experimental methodology used to study the contact mechanics of a rigid, rough surface and a compliant, nominally flat surface using digital image correlation (DIC). The rough surface was produced by 3-D printing PMMA and the flat surface was produced with transparent PDMS (silicone rubber). The deformation of the speckled top surface (contact) of the PDMS was measured via DIC viewed through the transparent media. Four different PDMS formulations with moduli ranging from 64 to 2120 kPa were used in the experiment program to cover a wide range of modulus normalized loads. The deformation of the contact surface and depth of penetration versus normalized load were measured. The results were overlaid with previous measurements of contact area and complemented them extremely well. Additionally, it was shown that scaling laws associated with such contact mechanics problems extend many length scales. 

  • 47.
    Saeidpour, Mahsa
    et al.
    RISE Research Institutes of Sweden, Materials and Production, Manufacturing Processes.
    Svenningsson, Roger
    RISE Research Institutes of Sweden, Materials and Production, Manufacturing Processes.
    Gotthardsson, Ulf
    RISE Research Institutes of Sweden, Materials and Production, Manufacturing Processes.
    Farre, Sten
    RISE Research Institutes of Sweden, Materials and Production, Manufacturing Processes.
    Thermal Properties of 3D-Printed Sand Molds2022In: International Journal of metalcasting, ISSN 1939-5981, E-ISSN 2163-3193, Vol. 16, p. 252-Article in journal (Refereed)
    Abstract [en]

    Specific heat capacity (Cp), density (ρ), and thermal conductivity (λ) of phenolic-bonded 3D-printed sand (3DPS) molds have been determined in the temperature range of 20–1400 °C using differential scanning calorimeter (DSC), dilatometer, and hot wire method. The results have been used to simulate the thermal gradient in a sand mold during casting aluminum using a commercial simulation software. The simulated results have been compared with laboratory-measured results and simulated results using the software’s database for conventional mold making. Our results show that available database for sand thermal properties cannot explain the thermal gradient in 3DPS molds and this manufacturing process affects the thermal properties of the mold compared to traditional mold making. It is necessary to collect data for a variety of 3D-printed sand molds to ensure accurate modeling simulation in the foundry industry. © 2021, The Author(s).

  • 48.
    Sibeck, Lennart
    RISE - Research Institutes of Sweden, Swerea, Swerea SWECAST.
    Högpresterande gjutna aluminiumkomponenter2017Report (Other academic)
    Abstract [en]

    The project is a continuation and reporting of 3 year G projects in high performance Al alloys, HPAL.

    The work has focused on gaining knowledge especially in two areas; how to increase the strength and toughness of commercial Al-Si alloys at elevated temperatures and at room temperature. A literature study has shown how to achieve very good properties through the addition of various alloy additions and the use of customized alloys. In this project the starting point has been

    conventional alloys, and better properties would be achieved both by optimizing alloying elements and by minimizing defect levels with improved gating system.

    A new test specimen model was designed in CAD. To show the influence of the melt flow on defects, and hence strength, the model was made in two versions; good resp. less good injection system. Sand moulds were produced using a 3D sand printer. The results of the tensile test became unexpected; the difference between the groups was very small.

    In the work of alloy with improved ductility, an alloy from the literature was chosen, using Cr to partially replace Mg. As starting alloy, AlSi7Mg was selected. Test specimens were produced in a gradient furnace, where a controlled solidification helps to minimize defects. The result shows that the Cr addition gave a slight increase in toughness, but after conventional aging, a severe reduction in strength was achieved. Aging at longer times gave strength comparable to the basic alloy without Cr, but lower than the alloy from literature.

    Directional solidification trials has illustated the importance of silicon as an alloying element on the mechanical properties at elevated temperature (230 C) for an Al-Si9-Cu3-Fe-alloy. An increase of silicon from 9,1 to 12,4 % improves the mechanical properties at room temperature as well as at elevated temperatures. Compared to the base-alloy EN AC 46000 (STENAL 460) the increase in yield strength, ultimate tensile strength and fracture elongation was 49, 17 and 20 % respectively at 230 C. The corresponding increase at room temperature was 16, 22 and 69 % respectively. A Master Thesis work at Jönköping University demonstrate the influnce of silicon, cobolt and nickel on the elevated temperature mechanical properties for Al-Si-alloys.

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  • 49.
    Sjögren, Torsten
    et al.
    RISE Research Institutes of Sweden, Materials and Production, Manufacturing Processes.
    Hall, Stephen
    Lund University, Sweden.
    Elmquist, Lennart
    Xylem Water Solutions Manufacturing AB, Sweden.
    Dartfeldt, Erik
    RISE Research Institutes of Sweden, Materials and Production, Applied Mechanics.
    Larsson, Emanuel
    RISE Research Institutes of Sweden, Bioeconomy and Health, Agriculture and Food.
    Majkut, Marta
    ESRF European Synchrotron Radiation Facility, France.
    Elfsberg, Jessica
    Scania CV AB, Sweden.
    Skoglund, Peter
    Scania CV AB, Sweden.
    Engqvist, Jonas
    Lund University, Sweden.
    In situ analysis of cast irons mechanical behaviour using synchrotron x-ray tomography and 3DXRD2020Conference paper (Refereed)
    Abstract [en]

    When subjecting cast irons to mechanical loading the deformation and damage mechanisms occur on a microstructural level and are dependent on the inherent microstructure. A deeper understanding of the relation between the different microstructural constituents and the macroscopic mechanical behaviour would be beneficial in material development efforts and for the ability to design and cast components with tailored properties. Traditionally, microscopy examinations on sectioned cast iron samples have been used when analysing the microstructure in cast irons. Since all microstructural heterogeneity is in three-dimensions (3D), methods that provide a three-dimensional characterisation are essential for a deeper understanding of, both the microstructural features as well as the deformation and damage of cast irons. Therefore, different cast iron grades have been studied using synchrotron X-ray tomography and 3D x-ray diffraction (3DXRD) at ESRF in Grenoble, France. The samples were stepwise loaded and unloaded in-situ at in the tomography/3DXRD set-up to study the deformation with regard to microstructural constituents and the microstructural evolution in 3D. Based on the 3D tomography image sequences, digital volume correlation (DVC) was used for full strain field analysis and for the analysis of damage and deformation mechanisms. In addition, 3DXRD data were analysed to provide details on the lattice parameters and lattice strain of individual ferrite grains. This work shows the possibilities of such synchrotron experiments for advanced study of the mechanical behaviour of cast iron.

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  • 50.
    Srivastava, Sumit
    et al.
    RISE Research Institutes of Sweden, Built Environment, Infrastructure and concrete technology. University of Oulu, Finland.
    Cerutti, Michela
    University of Oulu, Finland; Politecnico di Milano, Italy.
    Nguyen, Hoang
    University of Oulu, Finland.
    Carvelli, Valter
    Politecnico di Milano, Italy.
    Kinnunen, Paivo
    University of Oulu, Finland.
    Illikainen, Mirja
    University of Oulu, Finland.
    Carbonated steel slags as supplementary cementitious materials: Reaction kinetics and phase evolution2023In: Cement & Concrete Composites, ISSN 0958-9465, E-ISSN 1873-393X, Vol. 142, article id 105213Article in journal (Refereed)
    Abstract [en]

    With increasing interest in utilizing metallurgical slags for mineral carbonation, there is a need to find applications for carbonated slags. The scope of this study is to explore the utilization potential of carbonated steel furnace slags (SFS) as supplementary cementitious materials (SCM) to produce low-CO2 cement-based materials. Two different types of SFS are studied with comparable amounts of major oxides but significantly different mineral phase compositions. In the first phase of the study, several parameters that affect the CO2 uptake during mineral carbonation are considered (temperature, CO2 pressure, particle size, and duration) for the two slags namely, basic oxygen furnace slag (BOFS) and desulfurized slag (DeSS). Among the two slags, the DeSS exhibited significantly higher degrees of carbonation than BOFS, and the higher carbonation of DeSS is attributed to the presence of Ca as Ca(OH)2 rather than Ca–Si in BOFS. For both the slags, increase in temperature and CO2 pressure generally led to increase in the degree of carbonation. In the second phase of the study, 30 wt% of white Portland cement (WPC) was replaced by carbonated slags (used as SCM) in the cement mixture. The cement mixture with the BOFS carbonated at 60 °C and 1 bar CO2 pressure, as SCM, exhibited compressive strength comparable with that of WPC. Higher degrees and rates of carbonation under different conditions appears to have reduced their reactivities as SCM. © 2023 The Author(s)

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