Effect of an improved multistage thermo-mechanical processing on microstructure and mechanical property of TiB₂/Al-Cu composites

An improved multistage thermomechanical processing including multitemperature rolling and solution heat treatment, severe cold rolling and short-time aging heat treatment, of in-situ TiB2/Al-Cu composites have been proposed to modify matrix grain size, TiB2 particle distribution and precipitates. The average grain size of multitemperature rolling process was about 2 times smaller than that of conventional high temperature rolling. Additional, severe cold rolling prior to aging heat treatment was beneficial to form homogeneous distribution TiB 2 particles. The strength and ductility of TiB 2 /Al-Cu composites were significantly increased by the improved multistage thermomechanical processing due to the formation of finer recrystallized grains, more homogeneous distribution of TiB 2 particles and finer aging precipitates.