Compressive Behavior of Extruded SiCw/AZ91 at Temperatures close to and above the Solidus of the Matrix Alloy

Abstract

Compressive deformation behaviors of extruded SiCw/AZ91 were investigated in Gleeble-1500 thermal simulator at temperatures from 743 K to 783 K and strain rates from 6.4×10-2 s-1 to 1.0×101s-1. Results showed that high strain rate sensitivity (~0.5) occurred during compression; deformation activation energy normalized by threshold stress was higher than the lattice self-diffusion activation energy of magnesium. Dynamic recovery (DRV) and dynamic recrystallization (DRX) took place during compression, which refined the grains. The increase of deformation energy was attributed to non-basal planes slip and climbing of dislocations and also the presence of liquid phase.

Microstructure and mechanical property of the ECAPed Mg2Si/Mg composite

“…Microstructures in Mg matrix composites must therefore be improved to satisfy the high performance applications. It has been widely reported that refinement and homogenization of the reinforcement and as well the matrix grains through thermal-mechanical processing, such as conventional extrusion, rolling, subsequent heat treatment, etc., can effectively improve the mechanical property of Mg matrix composites [4][5][6][7][8][9].…”