Fatigue analysis of shot peened smooth and notched steel specimens

Author:  Bagherifard, Pariente, Guagliano and Bandini
Source:  Conf Proc 2011: ICSP-11 South Bend, IN USA (pgs. 93-97)
Doc ID:  2011015
Year of Publication:  2011
Abstract:  
Abstract Shot peening effects are mainly related to its ability to induce compressive residual stresses and work-harden the surface layer of material. It is well-recognized that the extent of these latter effects is essentially correlated to the process parameters, however an approach able to suggest the optimal choice of the peening parameters with respect of the treated material, component geometry and its in-service conditions is still lacking. In particular, this is true for not surface hardened materials. In this paper smooth and notched specimens of a low-alloy quenched and tempered steel are shot peened by different combination of peening parameters, to assess the influence of the process parameters on the fatigue strength. The results are elaborated by defining an approach able to estimate the fatigue limit with respect of the specimen geometry and the way the treatment is performed. Keywords: Fatigue, shot peening, residual stresses, 40NiCrMo7 steel.