Abstract
In superplastic deformation the fracture is generally associated with the cavitation and the superplastic elongation strongly depends on the level of internal cavitation during superplastic flow. Cavities occur at triple junction of grain boundaries in superplastic deformation. From the microstructural point of view, grain boundary characteristics may affect the cavitation. However the influence of grain boundary characteristics on cavitation during superplastic flow has not been clarified yet. In this study, cavitation behavior attributed to grain boundary characteristics was investigated. The materials used for this study were 7475 aluminum alloy processed by powder metallurgy (P/M7475). Grain boundary characteristics were inspected by orientation imaging microscopy (OIM). In P/M7475, the dynamic recrystallization occurred during deformation. This microstructural evolution may influence on cavitation in triple junction of grain boundaries during superplastic deformation.
