著者

Yoshikazu Matsuoka Tatsuya Iwasaki Nobuo Nakada Toshihiro Tsuchiyama Setsuo Takaki

出版者

The Iron and Steel Institute of Japan

雑誌

ISIJ International (ISSN:09151559)

巻号頁・発行日

vol.53, no.7, pp.1224-1230, 2013 (Released:2013-08-20)

参考文献数

14

被引用文献数

139 174

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In order to clarify the grain size dependence of mechanical stability of austenite, deformation-induced martensitic transformation behavior was investigated on uniaxial tensile deformation in a metastable austenitic stainless steel (Fe–16%Cr–10%Ni) with the grain size controlled from 1 to 80 μm. In addition, crystallographic characteristics of deformation-induced martensite were analyzed by means of the EBSD (electron backscattering diffraction) method to discuss the variant selection rule. It was found that mechanical stability of austenite is independent of its grain size, although thermal stability of austenite is remarkably increased by grain refinement. Some special martensite variants tend to be selected in an austenite grain on the deformation-induced martensitic transformation (near single-variant transformation), and this results in the formation of a texture along tensile direction. This suggests that the most advantageous variants are selected in the deformation-induced martensitic transformation to release tensile strain and leads to the grain size independence of mechanical stability of austenite.