長周期積層型マグネシウム合金の圧縮特性とその変形組織

抄録

Compression properties and deformation microstructure of a Mg_<85>Ni_6Y_9 (at. %) cast alloy were investigated. Yield strength of the Mg_<85>Ni_6Y_9 cast alloy was 365MPa which was higher than that of AZ91D. Kink deformation were frequently observed in the long period stacking ordered (LPSO) phase after compression test at room temperature (R.T). Also, the basal plane of the LPSO phase has tendency to orient a compression plane by compression test at R.T. It was considered that the basal texture of the LPSO phase is difficult compare with pure-Mg, due to introduce a kink formation. Although the yield strength of the Mg_<85>Ni_6Y_9 cast alloy decreased with increasing of test temperature, high yield strength above 200MPa was maintained at 573K. The LPSO phases with grain size of about 10μm were observed after compression test at 793K with strain rate of 4.2×10^<-3> S^<-1>. This result indicated that dynamic re-crystallization of the LPSO phase occurred at 793K.