Laser Shock Peening for Fatigue Resistance

Abstract

Laser shock peening is developing into a commercial surface enhancement process for increasing the fatigue life of metal components. The process produces deep residual compressive stresses into treated surfaces which inhibit the initiation and propagation of fatigue cracks. The process has been particularly effective in increasing the resistance to foreign object damage in fan and compressor blades of aircraft gas turbine engines. However, the potential application of this process is much broader, encompassing automotive, tooling and dies, and others. Significant effort is being made to lower the cost and increase the throughput of the process, to make it an affordable process for many more applications. This describes the process and reviews the progress being made in the technology, both in material property enhancement and use of the process, and towards reducing cost and increasing throughput.