Effect of laser shock processing on stress corrosion cracking behaviour of AZ31 magnesium alloy at slow strain rate

Abstract

An investigation was performed to evaluate the effect of laser shock processing (LSP) on AZ31 magnesium alloy using the slow strain rate tensile test. Microstructure revealed that a fine grained structure was obtained by LSP. X-ray diffraction showed that high compressive residual stress occurred at the surface after LSP. Meanwhile, the tensile strength of the LSP samples was improved. The stress corrosion cracking behaviour was examined, including both the base material and the LSP samples in air and 3·5%NaCl solution respectively. Test results demonstrated that the AZ31 Mg alloy after LSP exhibits higher stress corrosion cracking resistance than the base material.

Keywords:

• Magnesium
• Alloy
• SEM
• Stress corrosion

The authors gratefully acknowledge the financial support provided by the Natural Science Foundation of China (no. 51175231) and Jiangsu Provincial Key Laboratory for Science and Technology of Photon Manufacturing (no. GZ2011001).