Critical Conditions of Dynamic Recrystallization for B4Cp/6061Al Composite

Flow behavior and dynamic recrystallization (DRX) critical conditions of 25vol% B4Cp/6061Al composite were investigated by isothermal compression tests at temperatures ranging from 350 to 500 °C with strain rates of 0.001 to 1 s−1. The stress-strain curves show that DRX is the main softening mechanism of the composite, and an Arrhenius-type equation is developed using peak stress. Based on the strain hardening rate curves (θ-σ), the critical strain (ɛc) and critical stress (σc) are identified to express the initiation of DRX. The results indicate that there is a liner relationship between σc and σp:σc=0.8374σp−0.33708. The Zener-Hollomon parameter was also introduced to describe the effect of deformation conditions on critical conditions: ɛc=2.39×10−4Z0.11022. In addition, the steady-state strains (ɛss) were determined by the θ-ɛ curves, and then the DRX diagram was established.