Heat Treatment of Metals ›› 2021, Vol. 46 ›› Issue (9): 247-251.DOI: 10.13251/j.issn.0254-6051.2021.09.044

• SURFACE ENGINEERING • Previous Articles     Next Articles

Effect of laser shocking on surface integrity of 690 high strength steel

Cao Chen1, Huang Chunling2, Cao Yupeng1,2, Yang Yang3, Yang Cong1   

  1. 1. School of Mechanical Engineering, Nantong University, Nantong Jiangsu 226019, China;
    2. Jiangsu Five Star Bellows Co., Ltd., Taizhou Jiangsu 225300, China;
    3. Nantong Zhenhua Heavy Equipment Manufacturing Co., Ltd., Nantong Jiangsu 226017, China
  • Received:2021-04-22 Online:2021-09-25 Published:2021-12-09

Abstract: In order to study the effect of laser shocking treatment on the surface integrity of 690 high strength steel, pulsed lasers with different power densities were used to shock the steel specimens. With the help of optical profiler, X-ray stress meter, hardness tester and transmission electron microscope, the surface three-dimensional morphology, hardness, residual stress and microstructure of the 690 high strength steel before and after laser shocking were measured and analyzed. The results show that after laser shocking with different power densities, the surface roughness of the specimen increases; with the increase of laser power density, the maximum height Ry of the specimen surface profile increases from 1.814 μm to 3.247 μm. After laser shocking with different power densities, the average residual stress of the specimen increases from -122 MPa to -296 MPa, and the average microhardness increases from 277 HV0.1 to 355 HV0.1. Compared with the specimen without laser shocking, the laser shocking treatment makes the surface grains of the 690 high strength steel continue to be refined, and the greater the power density, the smaller the surface grain size of the steel.

Key words: 690 high strength steel, laser shocking, surface strengthening, microstructure, residual stress

CLC Number: