Effect of laser shock peening on microstructure and wear resistance for 15-5 PH stainless steel
Jiajun Wu, Xingze Lin, Youbin Lai, Wangwang Ding, Jibin Zhao, Hongchao Qiao
Abstract
Laser shock peening (LSP) is an advanced surface modification technology that can improve the mechanical properties of metallic parts effectively. In this work, the 15-5PH stainless steel was selected as experimental material, and the experimental samples were treated by LSP with the laser energy of 5 J and 8 J, pulse width of 15 ns, and laser beam spot diameter of 3 mm. The mechanical properties, microstructural evolution, and wear resistance of experimental samples before and after the LSP treatment were investigated. The experimental results indicated that after the LSP treatment, the compressive residual stress was induced in the near-surface and the surface compressive residual stress was increased with laser energy. The microhardness of experimental samples were increased with laser energy, too. Since the mechanical properties improvement, the wear rate of the experimental samples were decreased, showing the better wear resistance after the LSP. In addition, the enhancement of wear resistance mechanism was systematically discussed.