Creep Deformation of Short Alumina Fiber-Reinforced Al and 6061 Alloy

Abstract

The stress and temperature dependences of minimum creep rate and θ parameters in the θ-projection concept were examined on a 6061 Al matrix composite reinforced with 18 vol% short alumina fibers and compared with those of an aluminum matrix composite reinforced with the same short alumina fibers. The temperature dependences of creep rates and rate parameters of the Al matrix composite were controlled by the lattice diffusion of aluminum, while those of the 6061 Al matrix composite showed much higher temperature dependence than expected from the lattice diffusion of aluminum. It is proposed that the anomalously high activation energies for creep deformation, which have also been reported in some researches on the creep of 6061 Al matrix composites, is related to the effects of precipitation in the 6061 Al matrix.