About this Abstract |
Meeting |
2020 TMS Annual Meeting & Exhibition
|
Symposium
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Additive Manufacturing: Advanced Characterization with Synchrotron, Neutron, and In Situ Laboratory-scale Techniques
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Presentation Title |
Microscale Residual Stresses in Additively Manufactured Stainless Steel |
Author(s) |
Yin Zhang, Ting Zhu, Wen Chen, Morris Wang |
On-Site Speaker (Planned) |
Yin Zhang |
Abstract Scope |
Additively manufactured (AM) metallic materials commonly possess substantial microscale internal stresses. However, the impact of these residual stresses on the mechanical behaviour remains largely unexplored. Here we combined in-situ synchrotron X-ray diffraction (SXRD) experiments and computational modelling to quantify the lattice strains in different families of grains with specific orientations and associated residual stresses in AM 316L stainless steel. The results reveal the effects of elastic anisotropy, progressive yielding and work hardening on the behaviours of lattice strains. We also measured pronounced tension-compression asymmetries in yield strength and work hardening. Such asymmetries are associated with the back stresses that originate from heterogeneous dislocation distributions and resultant intragranular residual stresses. Furthermore, stress-relief heat treatment was shown to reduce the tension-compression asymmetries as well as the magnitude and non-linearity of lattice strains. This work establishes the mechanistic connections between the microscale residual stresses and mechanical behaviour of AM stainless steel. |
Proceedings Inclusion? |
Planned: Supplemental Proceedings volume |