Finite Elements Model of Shot Peening, Effects of Constitutive Laws of the Material

Author:  Rouhaud Ouakka Ould Chaboche Fran
Source:  Conf Proc: ICSP-9 (pg 107-112)
Doc ID:  2005059
Year of Publication:  2005
Abstract:  
ABSTRACT While very useful to understand the phenomena at hand, experiments can be very costly and time consuming if done for the purpose of setting a new set of shot peening parameters for the treatment of a new part. In the last 15 years, many finite element models have been proposed. Existing simulations show their efficiency to better understand the mechanism of residual stress introduction and better evaluate the influence of the shot peening parameters on the residual stress profile although some discrepancies still remain. It is not necessary to say that the constitutive law chosen to model the shot peened material strongly influences the residual stress field obtained after finite element computation. In this paper, we wish to address the following question: Should the model take kinematic hardening into account? Indeed, with a kinematic hardening model, plastic effects can appear during unloading as well as during loading. It seems very likely that such effects do appear during shot peening. Further, kinematic hardening effects are particularly influential when the loading is cyclic. As the numbers of impacts at one location on a shot peened surface with a high coverage can be important, cyclic effects do occur during the process. We thus discuss the different options offered for constitutive laws with a presentation of numerical strategies for cyclic plasticity modeling and the residual stress field obtained.