Residual Stress and Deformation Induced by Laser Shock Peening on Titanium Alloys

Abstract : During operation, a turbojet can swallow foreign objects (birds, fragments, etc.). The damage induced by these objects is known as FOD (Foreign Object Damage), and can lead to the cracking of the fan blades. In order to reduce the costs of maintenance, engine manufacturers try to find a way to increase the fatigue life, after FOD, of the fan blades by introducing compressive residual stresses in some areas with a specific surface treatment: laser shock peening (LSP). [1] The aim of this study is to point out the effects of this new treatment. The following results were carried out on square-shaped samples of Ti-6A1-4V alloy (TA6V) and Ti-5Al-2Sn-2Zr-4Cr4Mo alloy (Til7).