|About this Abstract
||MS&T23: Materials Science & Technology
||Advances in Understanding of Martensite in Steels II
||In-situ Neutron Diffraction Analysis of Deformation-induced Transformation Behavior in High-strength and High-ductility Metastable Austenitic Stainless Steel Produced by Cold-rolling and Partitioning Method
||Yuta Matsumura, Goro Miyamoto, Yongie Zhang, Tadashi Furuhara, Yo Tomota
|On-Site Speaker (Planned)
Cold-rolled and partitioned 17Cr-5Ni-0.08C -0.1N (mass %) metastable austenitic stainless steel consists of tempered martensite (α') and carbon- and nitrogen- enriched retained austenite (γR). This steel achieves excellent strength with high-ductility and TS x TEl reaches 35000MPa.% owing to large Lüders elongation and deformation-induced martensitic transformation. It was found that apparent Lüders elongation increases with decreasing work-hardening rate right after the completion of Lüders elongation. To clarify the detail of deformation, the stress partitioning between α' and γR and martensitic transformation behavior accompanying deformation were analyzed using in-situ neutron diffraction at J-PARC BL19 TAKUMI. Larger Lüders elongation increases by suppression of deformation-induced transformation, and thus increasing stability of γR. Deformation-induced transformation occurs after yielding of γR, that causes stress partitioning to the harder α'. Work-hardening of martensite phase dominates the apparent work-hardening and, thus lower work-hardening of martensite would be an important factor to improve Lüders elongation.