Yang Li. Analysis of Residual Stress and Crack of Superalloy by Laser Shock Processing[J]. Special Casting & Nonferrous Alloys, 2016,36(6):644-646. DOI: 10.15980/j.tzzz.2016.06.025.
高温合金激光冲击处理后残余应力及裂纹分析
摘要
利用激光冲击处理技术对GH141高温合金表面进行了冲击
采用X射线衍射法对其冲击处理前后残余应力分布进行了测试
并观察了其冲击处理前后疲劳裂纹产生情况。结果发现
GH141高温合金在冲击处理前残余应力均表现为拉应力
应力值约为200 MPa
在经过激光冲击处理后残余应力均转变为压应力
应力值约为-400 MPa
且硬度提高了20%
2
5%。在冲击过程中
发现处理后疲劳裂纹明显减少
说明激光冲击能有效降低疲劳裂纹的萌生
提高疲劳寿命。
Abstract
The surface of GH141 superalloy was processed by laser shock processing(LSP)
and residual stress distribution was tested with X-ray diffraction(XRD)before and after the impact treatment
meanwhile
the fatigue crack was observed.Experiment results show that the residual tensile stress of GH141 superalloy reaches up to 200 MPa before impact treatment.After a LSP
residual stress is converted to compressive stress with fluctuations in-400 MPa and hardness is increased by 20%
2
5%.By comparing the fatigue crack before and after LSP
it is found that the fatigue crack is reduced significantly after LSP
which shows that the technique can reduce effectively the fatigue crack initiation