Study on Surface Properties of Big Tilling Depth Rotary Blade for Laser Shock Peening

Abstract

A stress concentration area of big tilling depth rotary blade with 350 mm turning radius is found by ANSYS, and is strengthened by laser shock peening (LSP). The surface properties of rotary blade for LSP, included residual stress, surface micrograph, microstructure and hardness, are researched in this article. The results show that microstructure density is higher after LSP, and the layer is smoother, then the stress concentration is decreased. Meanwhile, the hardness and residual stress of rotary blade surface layer are significantly increased. The average residual stress reaches 390.7 MPa, and the average Rockwell hardness number achieves 45.1 HRC. Measuring results of residual stress, surface micrograph, microstructure and hardness after LSP indicate that LSP can significantly improve the surface properties of rotary blade, and it provides a new basis for further mending surface quality and fatigue property of big tilling depth rotary blade.