Microstructure evolution and mechanical properties of TiB₂/Cu composites processed by equal channel angular pressing at elevated temperature

A Cu matrix composite with 5vol% TiB₂ particles produced by powder metallurgy was subjected to equal channel angular pressing (ECAP) for 4 passes at 513K to enhance the strength of the Cu matrix through grain refinement. The introduction of TiB₂ particles with the particle spacing comparable with particle size increased the effective strain and led to homogeneous deformation structure with low recrystallization nucleation propensity. The combination of high effective strain and low recrystallization nucleation driving force ensures continuous refinement of Cu matrix in the TiB₂/Cu composite during the ECAP process. The mechanical behavior of the composite was discussed in terms of the microstructure evolution of Cu matrix during ECAP at elevated temperatures.