Distribution of residual stress fields in TC6 blade by LSP

Abstract

The aim was to analyse distribution rule of residual stress fields in a TC6 titanium alloy blade with multiple impacts and different spot overlapping ratios by comparing the numerical simulation and laser shock processing (LSP) experiments results. A dynamic model based on the finite element method was presented to simulate multiple impacts and different spot overlapping ratios by single sided LSP with round laser spot, and the distribution rule of residual stress fields based on different process condition was described. Further, LSP experiments of multiple impacts and different spot overlapping ratios were executed to compare the simulation results by measuring and fractographic observation. The results indicated that simulated values were reasonable with experimental values, and the compressive residual stresses were greatly increased and driven deeper below the blade surface with multiple impacts and high spot overlapping ratios on the same spot.

Keywords:

• Laser shock processing
• Residual stress
• Multiple impact
• Spot overlapping ratio
• TC6 blade

The authors are grateful for the support provided by the Science and Technology Plan Project of Shaanxi Province, China (grant no. 2013K07-17), the Natural Science Foundation of Shaanxi Province, China (grant no. 2012JM8004) and the National Natural Science Foundation of China (grant nos. 51075327 and 51275407).