Hot deformation behavior and processing map of SiCp/2024Al composite

The hot deformation behavior of 30%SiCp/2024 aluminum alloy composites was studied by hot compression tests using Gleeble-1500D thermo-mechanical simulator at the temperatures ranging from 350~500 ℃ under strain rates of 0.01~10 s-1. The true stress-true strain curves were obtained in the tests. Constitutive equation and processing map were established. The results show that the flow stress decreases with the increase of deformation temperature at a constant strain rate, and increases with the increase of strain rate at constant temperature, indicating that composite is a positive strain rate sensitive material. The flow stress behavior of composite during hot compression deformation can be represented by a Zener-Hollomon parameter in the hyperbolic sine form. Its activation energy for hot deformation Q is 153.251 kJ/mol. To demonstrate the potential workability, the stable zones and the instability zones in processing map were identified and verified through micrographs. Considering processing map and microstructure, the hot deformation should be carried out at the temperature of 450 ℃ and the strain rate of 1 s-1. Copyright © 2014, Northwest Institute for Nonferrous Metal Research. Published by Elsevier BV. All rights reserved.