An Unsuitable Residual Stress State In Train Springs Originated By Shot Peening

Author:  Artaraz, F. and Beitia, S. Sanchez
Source:  Int. Journ. Fatigue, March, 1991, p. 165
Doc ID:  1991003
Year of Publication:  1991
Abstract:  
This article deals with the residual stresses originated by 'shot peening', and their influence on train springs during a lifetime of service. The spanish firm Construccion y Auxiliar de Ferrocarriles, S.A., rejected the springs they analysed for this purpose. The main reason was that cracks were observed in the springs by different fatigue tests after 200 hours under realistic service conditions. The residual stresses introduced by the 'shot peening' process are believed to be the cause of the above-mentioned result, as they do not correspond to those of a correctly executed treatment. Consequently, these springs are not appropriate for the primary suspensions of locomotives at 180 km h-1. Descriptors: Residual stresses; Shot peening; train springs; Lifetime