Characterization of internal stresses in Mg-Zn-Y alloy with multimodal microstructure by deformation operando neutron diffraction

Harjo, S.   ; Gong, W.   ; Yamasaki, Michiaki*; Kawasaki, Takuro   ; Aizawa, Kazuya  

An as-cast sample and two hot-extruded samples with different R values of MgZnY alloy, the Mg-LPSO alloy containing LPSO of about 25-vol%, were used in tensile deformation operando neutron diffraction experiments. Mg behaved as the soft phase and LPSO as the hard phase, and hot-extrusion improved the strength of both. At the R value of 5.0, dynamic recrystallization partly occurred in Mgg creating a bimodal microstructure, consisting of the deformed Mg microstructure and the recrystallized Mg microstructure. The yield strength of Mg was significantly improved due to the optimal effects of dislocation density accumulation and texture development in the deformed Mg microstructure, and grain refinement in the recrystallized Mg microstructure.