Method of Peening Airfoils and Thin Edged Workpieces

Author:  James W. Neal, Joseph F. Loersch
Source:  US Patent 4,426,867
Doc ID:  1981129
Year of Publication:  1981
Abstract:  
Shot peening of thin edges of workpieces which are subject to deformation damage by direct impacts is accomplished by rotating the workpiece edge near centerline through a particular angle measured from the normal to the shot streamline. The angle is sufficient to cause oblique blows on the centerline of the edge, but insufficient to cause direct impacts. Compressive stresses by the oblique blows provide residual compressive stresses along the centerline to the desired depth of stressing produced by shot at a reference location. Oscillatory rotation is preferably used to obtain even peening.