By means of XRD technique, Instron Tensile tester and TEM, the paper deals with the dislocation density in matrix around the whiskers, and microyield strength and yield strength for SiCw/p-Al and SiCw/6061Al composites after different annealing treatments. The results shows that the the dislocation density in matrix of SiCw/p-Al composites decreases with annealing temperature rising, while the microyield strength and yield strength of SiCw/p-Al increases. The dislocation density in matrix, microyield streng...