The impact of heat treatment on microstructure, residual stress, and mechanical behavior of laser powder bed fusion additively manufactured Ti–6Al–2Sn–4Zr–2Mo alloy
In the field of additive manufacturing (AM), a promising alloy that is gaining attention is the near-α Ti–6Al–2Sn–4Zr–2Mo (Ti6242) alloy. This alloy is known for its remarkable resistance to creep and corrosion at elevated temperatures. However, the production of Ti6242 components via Laser-based AM...
Saved in:
| Main Authors: | , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
Elsevier
2024-11-01
|
| Series: | Journal of Materials Research and Technology |
| Subjects: | |
| Online Access: | http://www.sciencedirect.com/science/article/pii/S2238785424024724 |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
| _version_ | 1850120192168820736 |
|---|---|
| author | Matin Vafaei Reza Ghanavati Abdollah Saboori Luca Iuliano |
| author_facet | Matin Vafaei Reza Ghanavati Abdollah Saboori Luca Iuliano |
| author_sort | Matin Vafaei |
| collection | DOAJ |
| description | In the field of additive manufacturing (AM), a promising alloy that is gaining attention is the near-α Ti–6Al–2Sn–4Zr–2Mo (Ti6242) alloy. This alloy is known for its remarkable resistance to creep and corrosion at elevated temperatures. However, the production of Ti6242 components via Laser-based AM technologies faced with several challenges, such as the formation of residual stress in the as-built state that originates from the nature of these processes. Therefore, this study has a dual objective: first, to evaluate the microstructure and residual stresses in the as-built Ti6242 produced through laser powder bed fusion. Secondly, to investigate the impact of a promising post heat treatment on mitigating residual stresses, inducing alterations in the microhardness of the Ti6242 alloy and its ductility, phase transformations and microstructure evolution. The as-built specimen exhibited a significant residual stress of 1357 MPa, which was caused by the pronounced temperature gradients experienced during the fabrication process. It is interesting to note that this promising post heat treatment was highly effective in eliminating 99% of the residual stress. After heat treatment, the amount of α′ present in the as-built specimen decreased. This resulted in the activation of diffusion of elements such as molybdenum, causing a proportion of the α′ to decompose into the more ductile α+β structure. Additionally, it is revealed that the microstructural changes and relieved stresses from the heat treatment process caused a lower microhardness and a higher ductility under compressive loading, as the elongation and toughness reached 20.5% and 23.255 kJ/mm3 in the heat-treated samples, respectively. The outcomes of this work facilitate the use of this alloy in the production of complex shape components through laser-based AM technologies. |
| format | Article |
| id | doaj-art-2f9d76e5d7654919bf5bd72015482703 |
| institution | OA Journals |
| issn | 2238-7854 |
| language | English |
| publishDate | 2024-11-01 |
| publisher | Elsevier |
| record_format | Article |
| series | Journal of Materials Research and Technology |
| spelling | doaj-art-2f9d76e5d7654919bf5bd720154827032025-08-20T02:35:25ZengElsevierJournal of Materials Research and Technology2238-78542024-11-01335731574310.1016/j.jmrt.2024.10.202The impact of heat treatment on microstructure, residual stress, and mechanical behavior of laser powder bed fusion additively manufactured Ti–6Al–2Sn–4Zr–2Mo alloyMatin Vafaei0Reza Ghanavati1Abdollah Saboori2Luca Iuliano3Department of Management and Production Engineering, Politecnico di Torino, Corso Duca degli Abruzzi 24, 10129, Torino, Italy; Integrated Additive Manufacturing Center (IAM@PoliTo), Politecnico di Torino, Corso Castelfidardo 51, 10129, Torino, ItalyDepartment of Management and Production Engineering, Politecnico di Torino, Corso Duca degli Abruzzi 24, 10129, Torino, Italy; Integrated Additive Manufacturing Center (IAM@PoliTo), Politecnico di Torino, Corso Castelfidardo 51, 10129, Torino, ItalyDepartment of Management and Production Engineering, Politecnico di Torino, Corso Duca degli Abruzzi 24, 10129, Torino, Italy; Integrated Additive Manufacturing Center (IAM@PoliTo), Politecnico di Torino, Corso Castelfidardo 51, 10129, Torino, Italy; Corresponding author. Department of Management and Production Engineering, Politecnico di Torino, Corso Duca degli Abruzzi 24, 10129, Torino, Italy.Department of Management and Production Engineering, Politecnico di Torino, Corso Duca degli Abruzzi 24, 10129, Torino, Italy; Integrated Additive Manufacturing Center (IAM@PoliTo), Politecnico di Torino, Corso Castelfidardo 51, 10129, Torino, ItalyIn the field of additive manufacturing (AM), a promising alloy that is gaining attention is the near-α Ti–6Al–2Sn–4Zr–2Mo (Ti6242) alloy. This alloy is known for its remarkable resistance to creep and corrosion at elevated temperatures. However, the production of Ti6242 components via Laser-based AM technologies faced with several challenges, such as the formation of residual stress in the as-built state that originates from the nature of these processes. Therefore, this study has a dual objective: first, to evaluate the microstructure and residual stresses in the as-built Ti6242 produced through laser powder bed fusion. Secondly, to investigate the impact of a promising post heat treatment on mitigating residual stresses, inducing alterations in the microhardness of the Ti6242 alloy and its ductility, phase transformations and microstructure evolution. The as-built specimen exhibited a significant residual stress of 1357 MPa, which was caused by the pronounced temperature gradients experienced during the fabrication process. It is interesting to note that this promising post heat treatment was highly effective in eliminating 99% of the residual stress. After heat treatment, the amount of α′ present in the as-built specimen decreased. This resulted in the activation of diffusion of elements such as molybdenum, causing a proportion of the α′ to decompose into the more ductile α+β structure. Additionally, it is revealed that the microstructural changes and relieved stresses from the heat treatment process caused a lower microhardness and a higher ductility under compressive loading, as the elongation and toughness reached 20.5% and 23.255 kJ/mm3 in the heat-treated samples, respectively. The outcomes of this work facilitate the use of this alloy in the production of complex shape components through laser-based AM technologies.http://www.sciencedirect.com/science/article/pii/S2238785424024724Additive manufacturingLaser powder bed fusionHeat treatmentMicrostructureResidual stressMechanical behavior |
| spellingShingle | Matin Vafaei Reza Ghanavati Abdollah Saboori Luca Iuliano The impact of heat treatment on microstructure, residual stress, and mechanical behavior of laser powder bed fusion additively manufactured Ti–6Al–2Sn–4Zr–2Mo alloy Journal of Materials Research and Technology Additive manufacturing Laser powder bed fusion Heat treatment Microstructure Residual stress Mechanical behavior |
| title | The impact of heat treatment on microstructure, residual stress, and mechanical behavior of laser powder bed fusion additively manufactured Ti–6Al–2Sn–4Zr–2Mo alloy |
| title_full | The impact of heat treatment on microstructure, residual stress, and mechanical behavior of laser powder bed fusion additively manufactured Ti–6Al–2Sn–4Zr–2Mo alloy |
| title_fullStr | The impact of heat treatment on microstructure, residual stress, and mechanical behavior of laser powder bed fusion additively manufactured Ti–6Al–2Sn–4Zr–2Mo alloy |
| title_full_unstemmed | The impact of heat treatment on microstructure, residual stress, and mechanical behavior of laser powder bed fusion additively manufactured Ti–6Al–2Sn–4Zr–2Mo alloy |
| title_short | The impact of heat treatment on microstructure, residual stress, and mechanical behavior of laser powder bed fusion additively manufactured Ti–6Al–2Sn–4Zr–2Mo alloy |
| title_sort | impact of heat treatment on microstructure residual stress and mechanical behavior of laser powder bed fusion additively manufactured ti 6al 2sn 4zr 2mo alloy |
| topic | Additive manufacturing Laser powder bed fusion Heat treatment Microstructure Residual stress Mechanical behavior |
| url | http://www.sciencedirect.com/science/article/pii/S2238785424024724 |
| work_keys_str_mv | AT matinvafaei theimpactofheattreatmentonmicrostructureresidualstressandmechanicalbehavioroflaserpowderbedfusionadditivelymanufacturedti6al2sn4zr2moalloy AT rezaghanavati theimpactofheattreatmentonmicrostructureresidualstressandmechanicalbehavioroflaserpowderbedfusionadditivelymanufacturedti6al2sn4zr2moalloy AT abdollahsaboori theimpactofheattreatmentonmicrostructureresidualstressandmechanicalbehavioroflaserpowderbedfusionadditivelymanufacturedti6al2sn4zr2moalloy AT lucaiuliano theimpactofheattreatmentonmicrostructureresidualstressandmechanicalbehavioroflaserpowderbedfusionadditivelymanufacturedti6al2sn4zr2moalloy AT matinvafaei impactofheattreatmentonmicrostructureresidualstressandmechanicalbehavioroflaserpowderbedfusionadditivelymanufacturedti6al2sn4zr2moalloy AT rezaghanavati impactofheattreatmentonmicrostructureresidualstressandmechanicalbehavioroflaserpowderbedfusionadditivelymanufacturedti6al2sn4zr2moalloy AT abdollahsaboori impactofheattreatmentonmicrostructureresidualstressandmechanicalbehavioroflaserpowderbedfusionadditivelymanufacturedti6al2sn4zr2moalloy AT lucaiuliano impactofheattreatmentonmicrostructureresidualstressandmechanicalbehavioroflaserpowderbedfusionadditivelymanufacturedti6al2sn4zr2moalloy |