| 1. |
- Aydin, Gökçe, et al.
(författare)
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Influence of laser metal deposition process parameters on a precipitation hardening stainless steel
- 2023
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Ingår i: Welding in the World. - : Springer. - 0043-2288 .- 1878-6669. ; 67:4, s. 1067-1080
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Tidskriftsartikel (refereegranskat)abstract
- The combination of corrosion resistance and mechanical properties of martensitic precipitation hardening stainless steels (MPHSS) makes them well suited for demanding applications in aerospace, high-pressure gas bottles, or in injection molding of corrosive plastics. Directed energy deposition methods and specifically the laser metal deposition process with powder as feedstock (LMDp) have the potential to be applied in the production of such components. It is well-known that the geometrical features of the deposited beads such as aspect ratio and dilution are crucial for process efficiency and deposition quality. Therefore, this work aims at understanding the influence of the process parameters and the resulting microstructure of a MPHSS modified PH 13-8Mo alloy when using LMDp. Design of experiment (DoE) was used to plan and analyze the influence and interaction of the different LMDp process variables in the geometry of the deposits. It was found that height, width, and depth were statistically significantly influenced by speed, while height was also considerably influenced by the powder feeding rate. In terms of laser power, it was the most significant factor for the width and the depth, but it did not significantly affect the height of the beads. The results showed that the as-deposited microstructure of the modified PH 13-8Mo under the LMDp conditions investigated in this work consists of a martensitic matrix with some amount of primary δ ferrite. The presence of a low amount of retained austenite and aluminum-enriched inclusions was confirmed. This work enhances the fundamental process and material understanding of LMDp of the modified PH 13-8Mo alloy as a first stage in the fabrication of additively manufactured components.
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| 2. |
- Aydin, Gökçe, et al.
(författare)
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Towards Laser Metal Deposition of Modified PH 13-8Mo Powder
- 2023
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Ingår i: Key Engineering Materials. - 1013-9826 .- 1662-9795. ; 964, s. 85-90
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Tidskriftsartikel (refereegranskat)abstract
- Modified PH 13-8Mo alloy exhibits a good combination of corrosion resistance and mechanical properties for demanding applications in aerospace, petrochemical, and tooling industries. Additive manufacturing, specifically the laser metal deposition process with powder as feedstock (LMDp), has the potential to be utilized in these industries. However, very limited knowledge on the LMDp of this alloy currently exists. The aim of this work was, therefore, to deposit a multi-track single layer of modified PH 13-8Mo alloy as a first step towards 3D geometries, and to analyze the resulting microstructure by using Optical Microscopy, Scanning Electron Microscopy, X-Ray Diffraction, Electron Backscatter Diffraction, and micro-hardness. It was found that the multitrack single layer was free from major defects. The microstructure was heterogeneous, and it consisted of a martensitic matrix and small amounts of δ ferrite, austenite, and AlN. The results of this research will be used to tailor the microstructure and properties of future 3D additively manufactured components.
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| 3. |
- Buruk, Oguz'Oz', et al.
(författare)
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Children in 2077: Designing children's technologies in the age of transhumanism
- 2020
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Ingår i: Conference on Human Factors in Computing Systems - Proceedings. - New York, NY, USA : ACM.
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Konferensbidrag (refereegranskat)abstract
- What for and how will we design children's technologies in the transhumanism age, and what stance will we take as designers? This paper aims to answer this question with 13 fictional abstracts from sixteen authors of different countries, institutions and disciplines. Transhumanist thinking envisions enhancing human body and mind by blending human biology with technological augmentations. Fundamentally, it seeks to improve the human species, yet the impacts of such movement are unknown and the implications on children's lives and technologies were not explored deeply. In an age, where technologies such as under-skin chips or brain-machine interfaces can clearly be defined as transhumanist, our aim is to reveal probable pitfalls and benefits of those technologies on children's lives by using the power of design fiction. Thus, main contribution of this paper is to create diverse presentation of provocative research ideas that will foster the discussion on the transhumanist technologies impacting the lives of children in the future.
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