Quantitative X-ray diffraction analysis of solute-enriched stacking faults in -Mg alloys based on peak asymmetry analysis

X線回折ピークの非対称性解析に基づく-Mg合金における積層欠陥の定量的解析

江草 大佑*; 眞鍋 怜*; 川崎 卓郎   ; Harjo, S.   ; 佐藤 成男*; 阿部 英司*

Egusa, Daisuke*; Manabe, Ryo*; Kawasaki, Takuro; Harjo, S.; Sato, Shigeo*; Abe, Eiji*

Based on X-ray diffraction analysis we attempt to quantify a volume fraction of stacking faults, which are essentially enriched by solute elements (solute-enriched stacking faults; SESFs) in Mg-Zn-Gd alloys with a hexagonal-close-packed () structure. We find that the SESFs with a local face-center-cubic stacking mostly occurs as a limited thickness less than several unit-cell dimensions, causing anisotropic broadening of the diffraction peaks including -component. By dealing the SESFs as intergrowth-like precipitates, we have successfully decomposed the asymmetric peak profile into the -matrix and the SESF peaks, by which the relevant volume fractions can be estimated in a highly quantitative manner.