Shot peening is a cold working process in which the surface of a part is bombarded with small spherical media called shots. This process results in a hemisphere of cold-worked material that is highly stressed in compression. Fuchs [
] and several other researchers have reported that the values of the compressive stresses are at least as high as 50% of the ultimate strength of the material. In the open literature there is little information of crack growth data through the residual stress fields generated by shot peening. Kocada et al [
] suggested that this is probably due to the fact that the observation of short crack initiation and propagation in a heavily deformed surface layer is very difficult to monitor. The focus of this investigation is on the fatigue crack growth rates of short cracks in the shot peened aluminum alloys.