抄録
Powder metallurgical aluminum alloys exhibit high strain rate superplasticity due to the very fine grains obtained by dynamic recrystallization. The superplastic behavior in dynamically recrystallized alloy is different from that in conventional superplastic materials. From the micro structural point of view, grain boundary characteristics may affect the deformation mechanism. However, the influence of microstructural change on deformation mechanism during superplastic flow has not been clarified yet in dynamically recrystallized alloys. In this study, deformation behavior during deformation attributed to grain boundary characteristics was investigated. The material used for this study was P/M7475 (7475 aluminum alloy processed by powder metallurgy). Grain boundary characteristics were inspected by orientation imaging microscopy (OIM). In P/M7475, the dynamic recrystallization occurred during the deformation. This microstructural change influences deformation mechanism during superplastic deformation.