Effect of Different Ablative Overlays on Residual Stresses Introduced in IN718 SPF by Laser Shock Peening
Abhishek Telang, Amrinder S. Gill, Gokul Ramakrishnan and Vijay K. Vasudevan
Laser shock peening (LSP) was performed on IN718 SPF superalloy by using two different kinds of ablative overlays: a black vinyl tape and an Aluminum tape. The effect of ablative overlays on residual stresses induced by LSP was investigated. Two different power densities were used to peen the samples and in-depth residual stresses measured using conventional X-ray difraction (XRD).. Results show that Aluminum tape overlay introduced 100 to 150 MPa higher compressive residual stresses in the material as compared with the vinyl tape.
Keywords: Superalloys; laser shock preening; residual stresses; X-ray difraction (XRD); ablation overlays