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Publications (8 of 8) Show all publications
Swaminathan, K., Olsson, J., Raza, T., Harlin, P. & Andersson, J. (2023). Characterization of Laser Powder Bed Fusion of Nickel-Based Superalloy Haynes 282. In: Eric A. Ott, Joel Andersson, Chantal Sudbrack, Zhongan Bi, Kevin Bockenstedt, Ian Dempster, Michael Fahrmann, Paul Jablonski, Michael Kirka, Xingbo Liu, Daisuke Nagahama, Tim Smith, Martin Stockinger, Andrew Wessman (Ed.), Proceedings of the 10th International Symposium on Superalloy 718 and Derivatives: . Paper presented at TMS Annual Meeting & Exhibition 2023 (pp. 553-570). Springer
Open this publication in new window or tab >>Characterization of Laser Powder Bed Fusion of Nickel-Based Superalloy Haynes 282
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2023 (English)In: Proceedings of the 10th International Symposium on Superalloy 718 and Derivatives / [ed] Eric A. Ott, Joel Andersson, Chantal Sudbrack, Zhongan Bi, Kevin Bockenstedt, Ian Dempster, Michael Fahrmann, Paul Jablonski, Michael Kirka, Xingbo Liu, Daisuke Nagahama, Tim Smith, Martin Stockinger, Andrew Wessman, Springer, 2023, p. 553-570Conference paper, Oral presentation with published abstract (Refereed)
Abstract [en]

Nickel-based superalloy Haynes 282 specimens were manufactured using the Laser Powder Bed Fusion process with a powder layer thickness of 60 and 90 microns to study the effect of laser power, laser scan speed, and hatch distance on the melt pool dimensions and porosity. The melt pool dimensions and porosity were measured at the center of the cubes parallel to the build direction. Variation of melt pool depth and overlap exist within the same sample signifying the scatter present in the process. Laser scan speed was found to be the most significant parameter for porosity and hatch distance was found to be the most significant parameter affecting the average melt pool overlap depth in the cubes built with 60 microns layer thickness. Interaction of speed and hatch distance was found to be the most significant parameter for porosity and Laser scan speed was the most significant parameter for average melt pool overlap depth in cubes built with 90 microns layer thickness. Comparison of measured responses with individual parameters provides partial trends of melt pool dimensions and porosity. As the heat input is captured better in line energy and area energy density, a better trend of the melt pool dimensions data and marginal trend of porosity in comparison with energy densities is discussed. The ratio of maximum length to minimum length of defects such as porosity and lack of fusion is measured to determine the shape of the defects and averaged to provide insight into the dominant shape of defect for a given set of parameters.

Place, publisher, year, edition, pages
Springer, 2023
Series
The Minerals, Metals & Materials Series (MMMS), ISSN 2367-1181, E-ISSN 2367-1696 ; 4
Keywords
Haynes 282, Laser powder bed fusion, Melt pool dimensions, High layer thickness, Process parameter study
National Category
Manufacturing, Surface and Joining Technology
Research subject
Production Technology
Identifiers
urn:nbn:se:hv:diva-20175 (URN)10.1007/978-3-031-27447-3_35 (DOI)2-s2.0-85161408360 (Scopus ID)978-3-031-27446-6 (ISBN)978-3-031-27447-3 (ISBN)
Conference
TMS Annual Meeting & Exhibition 2023
Available from: 2023-06-27 Created: 2023-06-27 Last updated: 2024-04-23Bibliographically approved
Karimi Neghlani, P., Sadeghi, E., Ålgårdh, J., Olsson, J., Hörnqvist Colliander, M., Harlin, P., . . . Andersson, J. (2021). Tailored grain morphology via a unique melting strategy in electron beam-powder bed fusion. Materials Science & Engineering: A, 824, Article ID 141820.
Open this publication in new window or tab >>Tailored grain morphology via a unique melting strategy in electron beam-powder bed fusion
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2021 (English)In: Materials Science & Engineering: A, ISSN 0921-5093, E-ISSN 1873-4936, Vol. 824, article id 141820Article in journal (Refereed) Published
Abstract [en]

This study presents a unique melting strategy in electron beam-powder bed fusion of Alloy 718 to tailor the grain morphology from the typical columnar to equiaxed morphology. For this transition, a specific combination of certain process parameters, including low scanning speeds (400-800 mm/s), wide line offsets (300-500 mu m) and a high number of line order (#10) was selected to control local solidification conditions in each melt pool during the process. In addition, secondary melting of each layer with a 90. rotation with respect to primary melting induced more vigorous motions within the melt pools and extensive changes in thermal gradient direction, facilitating grain morphology tailoring. Four different types of microstructures were classified according to the produced grain morphology depending on the overlap zone between two adjacent melt pools, i.e., fully-columnar (overlap above 40 %), fully-equiaxed (overlap below 15 %), mixed columnar-equiaxed grains, and hemispherical melt pools containing mixed columnar-equiaxed grains (overlap similar to 20-25 %). The typical texture was <001>; however, the texture was reduced significantly through the transition from the columnar to equiaxed grain morphology. Along with all four different microstructures, shrinkage defects and cracks were also identified which amount of them reduced by a reduction in areal energy input. The hardness was increased through the transition, which was linked to the growth of the.” precipitates and high grain boundary density in the fully-equiaxed grain morphology.

Place, publisher, year, edition, pages
ELSEVIER SCIENCE SA, 2021
Keywords
Additive manufacturing; Electron beam-powder-bed fusion; Melting strategy; Grain structure; Alloy 718
National Category
Manufacturing, Surface and Joining Technology Metallurgy and Metallic Materials
Identifiers
urn:nbn:se:hv:diva-17450 (URN)10.1016/j.msea.2021.141820 (DOI)000689220800002 ()2-s2.0-85111856337 (Scopus ID)
Note

Funding from the “European Regional Development Fund,” the “Simulation and Control of Material affecting Processes” (SiCoMap), and the “Sustainable Manufacturing Through Next-Generation Additive Process” (SUMAN-Next) projects, with funding from the KK foundation, are highly acknowledged

Available from: 2021-10-18 Created: 2021-10-18 Last updated: 2022-04-04
Goel, S., Bourreau, K., Olsson, J., Klement, U. & Joshi, S. V. (2020). Can Appropriate Thermal Post-Treatment Make Defect Content in as-Built Electron Beam Additively Manufactured Alloy 718 Irrelevant?. Materials, 13(3), Article ID 536.
Open this publication in new window or tab >>Can Appropriate Thermal Post-Treatment Make Defect Content in as-Built Electron Beam Additively Manufactured Alloy 718 Irrelevant?
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2020 (English)In: Materials, E-ISSN 1996-1944, Vol. 13, no 3, article id 536Article in journal (Refereed) Published
Abstract [en]

Electron beam melting (EBM) is gaining rapid popularity for production of complex customized parts. For strategic applications involving materials like superalloys (e.g., Alloy 718), post-treatments including hot isostatic pressing (HIPing) to eliminate defects, and solutionizing and aging to achieve the desired phase constitution are often practiced. The present study specifically explores the ability of the combination of the above post-treatments to render the as-built defect content in EBM Alloy 718 irrelevant. Results show that HIPing can reduce defect content from as high as 17% in as-built samples (intentionally generated employing increased processing speeds in this illustrative proof-of-concept study) to &lt;0.3%, with the small amount of remnant defects being mainly associated with oxide inclusions. The subsequent solution and aging treatments are also found to yield virtually identical phase distribution and hardness values in samples with vastly varying as-built defect contents. This can have considerable implications in contributing to minimizing elaborate process optimization efforts as well as slightly enhancing production speeds to promote industrialization of EBM for applications that demand the above post-treatments.

Keywords
additive manufacturing, electron beam melting, defects, microstructure, hardness, alloy 718, hot isostatic pressing, post-treatment
National Category
Manufacturing, Surface and Joining Technology
Identifiers
urn:nbn:se:hv:diva-14926 (URN)10.3390/ma13030536 (DOI)000515503100043 ()2-s2.0-85079600396 (Scopus ID)
Funder
Knowledge Foundation, 20160281
Available from: 2020-01-30 Created: 2020-01-30 Last updated: 2024-07-04
Balachandramurthi, A. R., Olsson, J., Ålgårdh, J., Snis, A., Moverare, J. & Pederson, R. (2019). Microstructure tailoring in Electron Beam Powder Bed Fusion Additive Manufacturing and its potential consequences. Results in Materials, 1
Open this publication in new window or tab >>Microstructure tailoring in Electron Beam Powder Bed Fusion Additive Manufacturing and its potential consequences
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2019 (English)In: Results in Materials, E-ISSN 2590-048X, Vol. 1Article in journal (Refereed) Published
Abstract [en]

Electron Beam Powder Bed Fusion process for Alloy 718 was investigated, in the sense of microstructural evolution with varying process conditions. The existence of a geometric relationship between the melt front and the processing parameters was observed. By understanding and capitalizing on this relationship, it was possible to obtain columnar, equiaxed or bimodal microstructure.

Place, publisher, year, edition, pages
Elsevier, 2019
Keywords
Alloy 718, Texture, Microstructure, Additive manufacturing, Powder bed fusion
National Category
Manufacturing, Surface and Joining Technology
Research subject
Production Technology; ENGINEERING, Manufacturing and materials engineering
Identifiers
urn:nbn:se:hv:diva-14331 (URN)10.1016/j.rinma.2019.100017 (DOI)
Available from: 2019-08-26 Created: 2019-08-26 Last updated: 2024-06-27Bibliographically approved
Tofeldt, O., Pierce, S., Smillie, G., Kerr, W., Flockhart, G., Macleod, C., . . . McMahon, D. (2018). Investigation of fundamental ultrasonic propagation characteristics in NDT of Electron Beam Melted additive manufactured samples: Inconel 718. In: : . Paper presented at 12th European Conference on Non-Destructive Testing (ECNDT 2018), June 11-15, Gothenburg, 2018 (pp. 1-4).
Open this publication in new window or tab >>Investigation of fundamental ultrasonic propagation characteristics in NDT of Electron Beam Melted additive manufactured samples: Inconel 718
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2018 (English)Conference paper, Published paper (Other academic)
Abstract [en]

New approaches for efficient NDT inspection of modern additively manufactured metallic components are required urgently to qualify and validate the next generation of metallic parts across a range of industries. Ultrasonic testing is a fundamental component of NDT for such additive manufacturing processes. This work studies the ultrasonic propagation characteristics of EBM manufactured sample coupons in Inconel 718material. Fundamental longitudinal and shear wave velocity measurements are experimentally measured in 3 orthogonal build directions of the sample coupons. Results show a dependency of the ultrasonic velocities and the build direction. The measured velocities are further verified in a phased array measurement showing successful results that highlights the potential of continued studies with synthetic apertures techniques.

Keywords
Propagagation and scattering, Ultrasonics
National Category
Metallurgy and Metallic Materials Composite Science and Engineering
Research subject
ENGINEERING, Manufacturing and materials engineering; Production Technology
Identifiers
urn:nbn:se:hv:diva-12915 (URN)
Conference
12th European Conference on Non-Destructive Testing (ECNDT 2018), June 11-15, Gothenburg, 2018
Projects
Suman-next 400151
Available from: 2018-09-18 Created: 2018-09-18 Last updated: 2018-09-18Bibliographically approved
Karimi Neghlani, P., Deng, D., Sadeghimeresht, E., Olsson, J., Ålgårdh, J. & Andersson, J. (2018). Microstructure Development in Track-by-Track Melting of EBM-Manufactured Alloy 718. In: Ott, E., Liu, X., Andersson, J., Bi, Z., Bockenstedt, K., Dempster, I., Groh, J., Heck, K., Jablonski, P., Kaplan, M., Nagahama, D. and Sudbrack, C. (Ed.), Proceedings of the 9th International Symposium on Superalloy 718 & Derivatives: Energy, Aerospace, and Industrial Applications. Paper presented at 9th International Symposium on Superalloy 718 & Derivatives, Energy, Aerospace, and Industrial Applications, Pittsburgh, Pennsylvania, USA, 3-6 June, 2018 (pp. 643-654). Springer
Open this publication in new window or tab >>Microstructure Development in Track-by-Track Melting of EBM-Manufactured Alloy 718
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2018 (English)In: Proceedings of the 9th International Symposium on Superalloy 718 & Derivatives: Energy, Aerospace, and Industrial Applications / [ed] Ott, E., Liu, X., Andersson, J., Bi, Z., Bockenstedt, K., Dempster, I., Groh, J., Heck, K., Jablonski, P., Kaplan, M., Nagahama, D. and Sudbrack, C., Springer, 2018, p. 643-654Conference paper, Published paper (Refereed)
Abstract [en]

Electron beam melting (EBM) is a powder-bed fusion process within the group of additive manufacturing (AM) technology that is used to fabricate high performance metallic parts. Nickel-Iron base superalloys, such as Alloy 718, are subjected to successive heating and cooling at temperatures in excess of 800 °C during the EBM process. Characterization of the dendritic structure, carbides, Laves and δ-phase were of particular interest in this study. These successive thermal cycles influence the microstructure of the material resulting in a heterogeneous structure, especially in the building direction. Hence, the aim of this study was to gain increased fundamental understanding of the relationship between the processing history and the microstructure formed within a single layer. Different numbers of tracks with equal heights were for this purpose produced, varying from one to ten tracks. All tracks used the same process parameters regardless of number and/or position. Microstructure characteristics (sub-grain structure, grain structure and phases) were analyzed by optical microscopy, scanning electron microscopy equipped with energy disperse spectroscopy and electron backscatter diffraction. The direction of dendrites changed in the overlap zones within the tracks due to re-melting of material in the overlap zone. The primary dendrite arm spacings slightly increased along multi-tracks owing to a slight decrease in cooling rate by addition of the next tracks. Epitaxial growth of grains were observed in all samples due to partial re-melting of grains in previous layers and surface nucleation was also found to occur in all tracks.

Place, publisher, year, edition, pages
Springer, 2018
Series
The Minerals, Metals & Materials Series, ISSN 2367-1181, E-ISSN 2367-1696
Keywords
Additive manufacturing, Electron beam melting, Alloy 718, Microstructure, Track-by-Track
National Category
Metallurgy and Metallic Materials Manufacturing, Surface and Joining Technology
Research subject
ENGINEERING, Manufacturing and materials engineering; Production Technology
Identifiers
urn:nbn:se:hv:diva-12345 (URN)10.1007/978-3-319-89480-5_42 (DOI)000445800500042 ()2-s2.0-85053834715 (Scopus ID)978-3-319-89479-9 (ISBN)978-3-319-89480-5 (ISBN)
Conference
9th International Symposium on Superalloy 718 & Derivatives, Energy, Aerospace, and Industrial Applications, Pittsburgh, Pennsylvania, USA, 3-6 June, 2018
Note

First Online: 13 May 2018

Available from: 2018-10-26 Created: 2018-10-26 Last updated: 2020-11-10Bibliographically approved
Goel, S., Olsson, J., Ahlfors, M., Klement, U. & Joshi, S. V. (2018). The Effect of Location and Post-treatment on the Microstructure of EBM-Built Alloy 718. In: Ott, E., Liu, X., Andersson, J., Bi, Z., Bockenstedt, K., Dempster, I., Groh, J., Heck, K., Jablonski, P., Kaplan, M., Nagahama, D. and Sudbrack, C. (Ed.), Proceedings of the 9th International Symposium on Superalloy 718 & Derivatives: Energy, Aerospace, and Industrial Applications. Paper presented at 9th International Symposium on Superalloy 718 & Derivatives, Energy, Aerospace, and Industrial Applications, Pittsburgh, Pennsylvania, USA, 3-6 June, 2018 (pp. 115-129). Springer
Open this publication in new window or tab >>The Effect of Location and Post-treatment on the Microstructure of EBM-Built Alloy 718
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2018 (English)In: Proceedings of the 9th International Symposium on Superalloy 718 & Derivatives: Energy, Aerospace, and Industrial Applications / [ed] Ott, E., Liu, X., Andersson, J., Bi, Z., Bockenstedt, K., Dempster, I., Groh, J., Heck, K., Jablonski, P., Kaplan, M., Nagahama, D. and Sudbrack, C., Springer, 2018, p. 115-129Conference paper, Published paper (Refereed)
Abstract [en]

Additive manufacturing (AM) of Ni-based superalloys such as Alloy 718 may obviate the need for difficult machining and welding operations associated with geometrically intricate parts, thus potentially expanding design possibilities and facilitating cost-effective manufacture of complex components. However, processing AM builds completely free from defects, which may impair mechanical properties such as fatigue and ductility, is challenging. Anisotropic properties, microstructural heterogeneities and local formation of undesired phases are additional concerns that have motivated post-treatment of AM builds. This work investigates the microstructural changes associated with post-treatment of Alloy 718 specimens produced by Electron Beam Melting (EBM) for as-built microstructures at 3 build heights: near base plate, in the middle of build and near the top of the build. Two different post-treatment conditions, hot isostatic pressing (HIP) alone and a combined HIP with solutionising and two-step aging were examined and compared to the results for the as-built condition. The influence of various post-treatments on minor phase distributions (δ, γ″, carbides), overall porosity, longitudinal grain widths and Vickers microhardness was considered. The HIP treatment led to significant reduction in overall porosity and dissolution of δ phase, which led to appreciable grain growth for both post-treatment conditions. The variation in hardness noted as a function of build height for the as-built specimens was eliminated after post-treatment. Overall, the hardness was found to decrease after HIP and increase after the full HIP, solutionising and aging treatment, which was attributed to dissolution of γ″ during HIP and its re-precipitation in subsequent heat treatment steps.

Place, publisher, year, edition, pages
Springer, 2018
Series
The Minerals, Metals & Materials Series, ISSN 2367-1181, E-ISSN 2367-1696
Keywords
Additive manufacturing, Electron beam melting, Alloy 718, HIP, Heat treatment, Microstructure, XRD, Hardness, δ, γ″, Carbide
National Category
Manufacturing, Surface and Joining Technology
Research subject
ENGINEERING, Manufacturing and materials engineering; Production Technology
Identifiers
urn:nbn:se:hv:diva-12346 (URN)10.1007/978-3-319-89480-5_6 (DOI)000445800500006 ()2-s2.0-85055988720 (Scopus ID)978-3-319-89479-9 (ISBN)978-3-319-89480-5 (ISBN)
Conference
9th International Symposium on Superalloy 718 & Derivatives, Energy, Aerospace, and Industrial Applications, Pittsburgh, Pennsylvania, USA, 3-6 June, 2018
Funder
Knowledge Foundation, 20160281
Available from: 2018-10-26 Created: 2018-10-26 Last updated: 2020-11-04Bibliographically approved
Augustsson, S., Olsson, J., Gustavsson Christiernin, L. & Bolmsjö, G. (2014). How to Transfer Information Between Collaborating Human Operators and Industrial Robots in an Assembly. In: Proceedings the NordiCHI 2014: The 8th Nordic Conference on Human-Computer Interaction: Fun, Fast, Foundational. Paper presented at NordiCHI '14 Proceedings of the 8th Nordic Conference on Human-Computer Interaction: Fun, Fast, Foundational (pp. 286-294). ACM Publications
Open this publication in new window or tab >>How to Transfer Information Between Collaborating Human Operators and Industrial Robots in an Assembly
2014 (English)In: Proceedings the NordiCHI 2014: The 8th Nordic Conference on Human-Computer Interaction: Fun, Fast, Foundational, ACM Publications, 2014, p. 286-294Conference paper, Published paper (Refereed)
Abstract [en]

Flexible human-robot industrial coproduction will be important in many small and middle-sized companies in the future. One of the major challenges in a flexible robot cell is how to transfer information between the human and the robot with help of existing and safety approved equipment. In this paper a case study will be presented where the first half focus on data transfer to the robot communicating the human's position and movements forcing the robot to respond to the triggers. The second half focuses on how to visualize information about the settings and assembly order to the human. The outcome was successful and flexible, efficient coproduction could be achieved but also a number of new challenges were found.

Place, publisher, year, edition, pages
ACM Publications, 2014
Keywords
coproduction, human-robot interaction, industrial assembly, information transfer
National Category
Robotics
Research subject
ENGINEERING, Manufacturing and materials engineering; Production Technology
Identifiers
urn:nbn:se:hv:diva-6874 (URN)10.1145/2639189.2639243 (DOI)2-s2.0-84911458351 (Scopus ID)978-1-4503-2542-4 (ISBN)
Conference
NordiCHI '14 Proceedings of the 8th Nordic Conference on Human-Computer Interaction: Fun, Fast, Foundational
Available from: 2014-10-20 Created: 2014-10-20 Last updated: 2020-01-17Bibliographically approved
Organisations
Identifiers
ORCID iD: ORCID iD iconorcid.org/0000-0001-5907-4061

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