(S235) Evaluation of dislocation density and work hardening behavior in austenitic steel by direct fitting method

摘要

Austenitic steels exhibit high work hardenability due to a low stacking fault energy (SFE). Although it is qualitatively known that dislocation accumulation is promoted when the SFE of austenite is low, there is little quantitative evidence because the Williamson-Hall (WH) method cannot be applied, owing to the elastic anisotropy in the X-ray diffraction planes for austenite. Recently, it was reported that the elastic anisotropy in WH plots can be corrected using the diffraction Young’s modulus (Direct Fitting (DF) method)1). This method is expected in a new evaluation technique because the micro-strain (ε) related to the dislocation density is easily obtained by the slope of the WH plots corrected by the DF method. In this study, the dislocation accumulation and work-hardening behavior in austenitic steels with different SFEs were evaluated by the DF method and the applicability of the ε obtained by the DF method is discussed.