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Zhu, B., Seifeddine, S., Jarfors, A., Leisner, P. & Zanella, C. (2019). A study of anodising behaviour of al-si components produced by rheocasting. Solid State Phenomena, 285, 39-44
Open this publication in new window or tab >>A study of anodising behaviour of al-si components produced by rheocasting
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2019 (English)In: Solid State Phenomena, ISSN 1012-0394, E-ISSN 1662-9779, Vol. 285, p. 39-44Article in journal (Refereed) Published
Abstract [en]

This paper aims to investigate the anodising behaviour of Al-Si components produced by rheocasting, to understand the effect of the surface liquid segregation (SLS) on the anodising response. The material investigated was EN AC 42000 Al-alloy with an addition of 150 ppm Sr. The component was rheocast and conventionally liquid cast for benchmarking. The RheoMetal™ process was used to prepare slurry and subsequently cast using a vertical pressure die casting machine. Prior to anodising, mechanical grinding was used as pre-treatment method for selected samples as comparison with components in the as-cast state. Anodising was performed on the components using a constant controlled voltage at 25 V, in 1 M H2 SO4, at room temperature. The duration of anodising was varied from 30 mins to 120 mins to examine the relationship between oxide layer thickness and the anodising time. The oxide layer was investigated and characterised. The results demonstrated that the presence of the SLS layer, which was enriched with alloying elements, had a significant influence on the anodising behaviour of the cast component. The oxide layer thickness of the components produced by rheocasting and fully liquid casting was measured and compared. The relations between the oxide layer thickness and anodising time, as well as the casting methods are presented and discussed in this paper..

Keywords
Anodising, Oxide layer, Rheocasting, Alloying elements, Die casting, Liquids, Silicon compounds, Surface segregation, Cast components, Liquid segregation, Mechanical grinding, Oxide layer thickness, Pretreatment methods, Vertical pressure, Aluminum alloys
National Category
Natural Sciences
Identifiers
urn:nbn:se:ri:diva-37718 (URN)10.4028/www.scientific.net/SSP.285.39 (DOI)2-s2.0-85059944290 (Scopus ID)9783035713732 (ISBN)
Note

 Funding details: Knowledge Foundation, 201000280, 20170066; Funding text 1: This research was supported by the Knowledge Foundation (CompCast project no. 201000280, CompCast Plus project no. 20170066)

Available from: 2019-02-01 Created: 2019-02-01 Last updated: 2019-02-08Bibliographically approved
Leisner, P. & Johansson, E. (2019). Aspects to be considered when making innovation out of promising research results in surface technology. Transactions of the Institute of Metal Finishing, 97(2), 67-72
Open this publication in new window or tab >>Aspects to be considered when making innovation out of promising research results in surface technology
2019 (English)In: Transactions of the Institute of Metal Finishing, ISSN 0020-2967, E-ISSN 1745-9192, Vol. 97, no 2, p. 67-72Article in journal (Refereed) Published
Abstract [en]

In the eyes of industrialists, scientists often exaggerate the economic potential of their findings. The industrialists know that developing a new technology to production is associated with uncertainty and risks. To elucidate the challenges faced by the surface treatment industry, this paper discusses aspects that should be considered when making innovation out of promising research results. The Technology Readiness Level (TRL) metric for assessing maturity of a technology is discussed and exemplified. Additional risks of fluid character such as legislation, price of raw material and customer expectations are also discussed. Even though, the subject is of general relevance, the present discussion refers to surface technology and examples are given from copper plating of printed circuit boards, and durable and cost-efficient coatings on electrical connectors.

Keywords
Electric connectors, Printed circuit boards, Cost-efficient, Customer expectation, Economic potentials, Electrical connectors, Research results, Surface technology, Technology readiness levels, Uncertainty and risks, Surface treatment
National Category
Natural Sciences
Identifiers
urn:nbn:se:ri:diva-38220 (URN)10.1080/00202967.2019.1561984 (DOI)2-s2.0-85062337067 (Scopus ID)
Available from: 2019-03-29 Created: 2019-03-29 Last updated: 2019-04-01Bibliographically approved
Mölmen, L., Lundblad, A. O., Fast, L., Zanella, C. & Leisner, P. (2019). Investigation of feed water impurities on life-time of PEMWE. In: : . Paper presented at 2nd International Conference on Electrolysis Loen, Norway - June 9-13, 2019. , Article ID 158.
Open this publication in new window or tab >>Investigation of feed water impurities on life-time of PEMWE
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2019 (English)Conference paper, Poster (with or without abstract) (Other academic)
Abstract [en]

With the introduction of fuel cell electric vehicles (FCEV), hydrogen gas produced without fossil fuels Is requiredto reduce the CO2 emissions. At the same time, the production of renewable energy is increasing. Waterelectrolysis to produce hydrogen with the use of electricity from renewable sources allows for storage of theenergy in the form of hydrogen. The gas can be utilized either back to the electric net or as fuel for FCEVs.However, the cost of water electrolysis systems needs to be reduced while the lifetime must be increased. Oneof the main limitations of the proton exchange membrane water electrolyser (PEMWE) system is the degradationof the membrane1. This limits the lifetime of the system and is expensive to replace. It has been shown thatimpurities from feed water and the degradation products from other component poison the membrane, loweringthe proton conductivity. Furthermore, metal ion impurities catalyse the formation of hydrogen peroxide at thecathode further contributing to irreversible membrane thinning2. In industrial systems, the water circulated tothe cells is purified to minimize the degradation. However, the purification limits the operating temperature ofthe systems and increases the total system cost2.The water quality used in most electrolysis cells today utilises ASTM type II deionized water. However, littleresearch is done on the limitations, and quantifying the reduction in efficiency dependent on the water quality.Dedigama et al.3 calculated the minimum flow needed, and further state that in industry, 5 times the necessaryflow of water is circulated to ensure proper wetting of the membrane. However, in research, an excess of wateris often used, up to 100 times higher flow than required, to exclude mass transport restrictions on thereactions3,4.Increasing temperature decreases the kinetic overpotential and increases the membrane conductivity4.However, also dissolution of the catalyst and degradation of the cell components increase with temperature.Furthermore, in industrial applications the maximum temperature of the water into the purification system is60°C5. Dependent on the aim of the research, experiments at temperatures as low as 25°C are performed to fitwith the industry, while others run at 80 or 90°C to probe the upper limits of current density and efficiency2.In this project we aim to analyse the effect of varying water purity on the membrane degradation in a single PEMelectrolysis cell test setup. Furthermore, the effect of changing temperature from 60 to 80°C on the impuritytolerance will be studied. The circulating feed water will be analysed with respect to conductivity, metal ion andfluorine concentration. A parallel “blank” system with only tubings, fittings etc will be assembled and comparedto the data measured from the electrolyser. Contaminating species will be added to the feed water to study theirimpact.

National Category
Engineering and Technology
Identifiers
urn:nbn:se:ri:diva-39775 (URN)
Conference
2nd International Conference on Electrolysis Loen, Norway - June 9-13, 2019
Available from: 2019-08-14 Created: 2019-08-14 Last updated: 2019-08-15Bibliographically approved
Leisner, P. & Nielsen, L. P. (2019). Offshoring and backshoring of surface finishing from the perspective of the Nordic countries. Transactions of the Institute of Metal Finishing, 97(2), 54-56
Open this publication in new window or tab >>Offshoring and backshoring of surface finishing from the perspective of the Nordic countries
2019 (English)In: Transactions of the Institute of Metal Finishing, ISSN 0020-2967, E-ISSN 1745-9192, Vol. 97, no 2, p. 54-56Article in journal (Refereed) Published
Abstract [en]

Backshoring of production to Western Europe has become an increasingly important trend after decades of offshoring. The subject is introduced by a general discussion followed by a specific analysis of the Nordic surface finishing industry. The main finding is that production quality is the main driver for backshoring of surface finishing. .

Keywords
finishing, Market trends, Scandinavia, supplier, surface technology, Nordic countries, Production quality, Surface finishing, Surface finishing industry, Surface treatment
National Category
Natural Sciences
Identifiers
urn:nbn:se:ri:diva-38221 (URN)10.1080/00202967.2019.1571261 (DOI)2-s2.0-85062368213 (Scopus ID)
Available from: 2019-03-29 Created: 2019-03-29 Last updated: 2019-03-29Bibliographically approved
Mölmen, L., Braun, M., Baumgärtner, M. & Leisner, P. (2019). Pt-P catalyst for fuel cells. In: : . Paper presented at 4th WORKSHOP e-MINDs, COST Action MP1407, Milano, 13-15/2, 2019.
Open this publication in new window or tab >>Pt-P catalyst for fuel cells
2019 (English)Conference paper, Oral presentation with published abstract (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.

National Category
Metallurgy and Metallic Materials
Identifiers
urn:nbn:se:ri:diva-39313 (URN)
Conference
4th WORKSHOP e-MINDs, COST Action MP1407, Milano, 13-15/2, 2019
Available from: 2019-07-02 Created: 2019-07-02 Last updated: 2019-07-03Bibliographically approved
Mölmen, L., Alexandersson, A. & Leisner, P. (2019). Surface technology should improve PEM fuel cell performance. Transactions of the Institute of Metal Finishing, 97(3), 112-114
Open this publication in new window or tab >>Surface technology should improve PEM fuel cell performance
2019 (English)In: Transactions of the Institute of Metal Finishing, ISSN 0020-2967, E-ISSN 1745-9192, Vol. 97, no 3, p. 112-114Article in journal (Refereed) Published
Abstract [en]

Leading industrial nations are investing in hydrogen technology as energy storage solution with fuel cells as the main converter to electric energy. Improvements in the performance of the key components: electrode catalyst, bipolar plates and polymer electrolyte membrane are needed to reduce costs for mass-market introduction. Consequently, surface technology has an essential role in meeting the goals. 

Place, publisher, year, edition, pages
Taylor and Francis Ltd., 2019
Keywords
bipolar plate, catalyst, corrosion, hydrogen, Catalysts, Fuel cells, Hydrogen storage, Polyelectrolytes, Bipolar plates, Electrode catalysts, Hydrogen technologies, Industrial nations, Market introduction, Polymer electrolyte membranes, Storage solutions, Surface technology, Proton exchange membrane fuel cells (PEMFC)
National Category
Natural Sciences
Identifiers
urn:nbn:se:ri:diva-38893 (URN)10.1080/00202967.2019.1596573 (DOI)2-s2.0-85065790068 (Scopus ID)
Note

Funding details: Horizon 2020; Funding details: Horizon 2020 Framework Programme, H2020; Funding text 1: This project has received funding from the European Union’s Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie grant agreement No 764977.

Available from: 2019-06-03 Created: 2019-06-03 Last updated: 2019-06-03Bibliographically approved
Zhu, B., Seifeddine, S., Jarfors, A. E. .., Leisner, P. & Zanella, C. (2018). A study of anodising behaviour of Al-Si componentsproduced by rheocasting. In: : . Paper presented at S2P2018, Shenzhen, China 22-24 October 2018.
Open this publication in new window or tab >>A study of anodising behaviour of Al-Si componentsproduced by rheocasting
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2018 (English)Conference paper, Oral presentation with published abstract (Other academic)
National Category
Metallurgy and Metallic Materials
Identifiers
urn:nbn:se:ri:diva-36950 (URN)
Conference
S2P2018, Shenzhen, China 22-24 October 2018
Available from: 2018-12-28 Created: 2018-12-28 Last updated: 2019-01-11Bibliographically approved
Leisner, P. & Zanella, C. (2018). Application of Assaf panel for evaluating throwing power of pulse reverse electroplating on complex geometries. Transactions of the Institute of Metal Finishing, 96(5), 258-264
Open this publication in new window or tab >>Application of Assaf panel for evaluating throwing power of pulse reverse electroplating on complex geometries
2018 (English)In: Transactions of the Institute of Metal Finishing, ISSN 0020-2967, E-ISSN 1745-9192, Vol. 96, no 5, p. 258-264Article in journal (Refereed) Published
Abstract [en]

The Assaf panel arrangement was used for evaluating pulse reverse plating processes and optimisation of the throwing power (TP) of complex three-dimensional (3D) geometries. Two different electroplating processes were investigated: an acid copper bath and a cyanide silver bath without additives. It has not been possible to establish a direct correlation factor for TP obtained with the Assaf panel and the 3D objects included in the trials. Nevertheless, the Assaf panel was found to be a useful tool for preliminary process parameter optimisation. The copper bath needs agitation to deposit coatings of good quality, whereas the silver bath obtains the best throwing power without agitation. The latter is probably due to inhibition by adsorbed cyanide.

Keywords
copper, pulse reverse, silver, Throwing power, Cyanides, Complex geometries, Correlation factors, Electroplating process, Process parameters, Pulse reverse plating, Three-dimensional (3D) geometry, Electroplating
National Category
Natural Sciences
Identifiers
urn:nbn:se:ri:diva-35202 (URN)10.1080/00202967.2018.1507331 (DOI)2-s2.0-85053235016 (Scopus ID)
Available from: 2018-10-10 Created: 2018-10-10 Last updated: 2019-03-06Bibliographically approved
Leisner, P., Hansen, Å. & Zanella, C. (2018). Applicationof Assaf panel for evaluating the throwing power of pulse reverse plating. In: : . Paper presented at 8th European Pulse Plating Seminar, Vienna 2 March 2018.
Open this publication in new window or tab >>Applicationof Assaf panel for evaluating the throwing power of pulse reverse plating
2018 (English)Conference paper, Oral presentation with published abstract (Other academic)
National Category
Manufacturing, Surface and Joining Technology
Identifiers
urn:nbn:se:ri:diva-36947 (URN)
Conference
8th European Pulse Plating Seminar, Vienna 2 March 2018
Available from: 2018-12-28 Created: 2018-12-28 Last updated: 2019-01-11Bibliographically approved
Leisner, P. (2018). Aspectsto be considered when making innovation out of promising research results insurface technology. In: : . Paper presented at 32th International Conference on Surface Modification Technologies (SMT32), San Sebastian 27-29 June 2018.
Open this publication in new window or tab >>Aspectsto be considered when making innovation out of promising research results insurface technology
2018 (English)Conference paper, Oral presentation with published abstract (Other academic)
National Category
Manufacturing, Surface and Joining Technology
Identifiers
urn:nbn:se:ri:diva-36948 (URN)
Conference
32th International Conference on Surface Modification Technologies (SMT32), San Sebastian 27-29 June 2018
Available from: 2018-12-28 Created: 2018-12-28 Last updated: 2019-03-06Bibliographically approved
Identifiers
ORCID iD: ORCID iD iconorcid.org/0000-0002-7095-1907

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