The Constitutive Model and Processing Map for in-situ 5wt% TiB2 Reinforced 7050 Al Alloy Matrix Composite

This study investigated the constitutive flow behavior and hot workability of in-situ 5wt% TiB2 reinforced 7050 Al alloy matrix composite by hot compression experiments. Based on the experimental results of flow curves, a constitutive model describing the relationship of the flow stress, true strain, strain rate and temperature is proposed. Substantially, it is found the constitutive equation of flow stress is dependent on the strain, strain rate and temperature. The coefficients (E.g., alpha, n, Q and InA) in the equation are functions of true strains. The results of the calculated values from constitutive equation are verified to well agree with the experimental values. Furthermore, the processing map of the composite is created in order to determine the hot processing domains. The optimum zones for hot workability and instability regions are identified. In instability domain, the microstructures display the main failure modes as the particle cracking and interface debonding.