CREEP DEFORMATION OF SHORT ALUMINA FIBER-REINFORCED AL AND 6061-ALLOY

The stress and temperature dependences of minimum creep rate and theta parameters in the theta-projection concept were examined on a 6061 Al matrix composite reinforced with 18 vol% short alumina fibers and com pared with those of an aluminum matrix composite reinforced with the s ame short alumina fibers. The temperature dependences of creep rates a nd rate parameters of the Al matrix composite were controlled by the l attice diffusion of aluminum, while those of the 6061 Al matrix compos ite showed much higher temperature dependence than expected from the l attice diffusion of aluminum. It is proposed that the anomalously high activation energies for creep deformation, which have also been repor ted in some researches on the creep of 6061 Al matrix composites, is r elated to the effects of precipitation in the 6061 Al