|About this Abstract
||2022 TMS Annual Meeting & Exhibition
||Ultrafine-grained and Heterostructured Materials (UFGH XII)
||H-27: Structural Evolution during Nanostructuring of Additive-manufactured 316L Stainless Steel by High-pressure Torsion
||Isshu Lee, Jae-Kyung Han, Xiaojing Liu, Yulia O. Kuzminova, Stanislav A. Evlashin, Klaus-Dieter Liss, Megumi Kawasaki
|On-Site Speaker (Planned)
This study investigates the significance of post-printing nanostructuring on structural evolution in an additive-manufactured 316L stainless steel through high-pressure torsion (HPT) at 6 GPa. A limited formation of an ε-martensite phase is observed in the nanostructured austenitic steel with an average grain size of 60 nm after 8-15 HPT turns. X-ray diffraction reveals significant structural changes by decreasing crystallite sizes and increasing micro-strains and lattice parameters even after 1/2 HPT turn. Significant strain gradients exist between the close-packed planes and out-of-close-packed-planes in the nanostructured steel, while such strain gradient was not observed in the as-printed sample. These drastic changes in structure are attributed to severe lattice distortion by the excess of dislocations and defects introduced during nanostructuring.
||Additive Manufacturing, Iron and Steel, Phase Transformations