The effect of SiC whiskers on the hot-deformation behavior of SiCw/AA2124 composites

Abstract

The hot-deformation behavior of composites consisting of an AA2124 matrix reinforced with 15 vol% of SIC whiskers has been studied over a temperature range of 200 to 530 degrees C and a strain rate range of 1.32 x 10(-3) to 2.38 s(-1). Detailed analyses of flow curves and deformed microstructures were made to identify the hot-recovery mechanism of the composites. The critical strain, epsilon(c), for dynamic recrystallization of the composites was also evaluated by the work-hardening rate, theta, and effective stress, sigma, from the flow curves. It was found that the hot-recovery mechanism of the composites was dynamic recrystallization and the addition of SiC whiskers promoted nucleation of the dynamic recrystallization. The relationship between the critical strain, epsilon(c), and peak strain, epsilon(p), of the composites was epsilon(c) approximate to 0.52 epsilon(p). (C) 1997 Elsevier Science Limited.