Study of Shot Peening (1st and 2nd reports)

On the shot peening process now effectively applied to automobile leaf springs, the authors have investigated the following points with two types of practical shot peening machines, namely the air basting and centrifugal types.1) The characteristic differences due to the two types of machines and the peening intensity effects.2) The effect of heating after shot peening.3) The reduction of produced residual stress by stress repeating.4) On stress peening.5) The effectiveness on the hot rolled surface.The results show that the fatigue properties of over peening, stress peening etc. can be, for the most part, explained by the residual stress produced within the surface layer which is about 0.05mm.