Abstract
In this paper, the generating mechanism of residual stress in work surface layers in the indenting process is discussed experimentally, in order to optimize the process conditions to produce the desired residual stress in blast processes. A static indenting process and a dynamic shot process using a steel ball against a workpiece (0.5%C annealed) were carried out, in order to clarify the generating mechanism and the shot speed effect on residual stress in blast processes. The quantity of the plastic flow in the dynamic shot process is greater than that of the static indenting process. In both processes, the tensile residual stress is generated below the piling-up area of the dimple shoulder. In addition the residual stress distribution in the inde nting process can be simulated approximately to that of the blast process, although shot speed influences dimple profiles however scarcely on residual stress.
