Abstract:AlN particulate reinforced 6061 aluminum alloy composite was fabricated by powder metallurgy method and hot-rolled after extrusion. Tensile strength and elongation at elevated temperature were measured by tensile test at initial strain rates between 10^-2s^-1and 100s^-1. The AlNp/6061Al composite exhibits anm-value of 0.42 and a maximum elongation of 450% at 863K. Differential scanning calorimeter was used to ascertain the possibility of any partial melting in the vicinity of optimum superplastic temperature. Partial melting resulting from solute segregation at interfaces has much influence on superplasticity of the composite. It is postulated that AlNp/matrix interface sliding occurs along with grain boundary in superplastic deformation.

Key words: superplasticity; aluminum matrix composite; AlN particulate