Shot peening simulation using discrete and finite element methods

Modeling shot peening process is very complex as it involves the interaction of metallic surfaces with a large number of shots of very small diameter. Conventionally such problems are solved using the finite element software (such as ABAQUS) to predict the stresses and strains. However, the number of shots involved and the number of elements required in a real-life components for a 100% coverage that lasts a considerable duration of peening make such an approach impracticable. Ideally, a method that is suitable for obtaining residual compressive stresses (RCS) and the amount of plastic deformations with the least computational effort seems a dire need. In this paper, an attempt has been made to address this issue by using the discrete element method (DEM) in combination with the finite element method (FEM) to obtain reasonably accurate predictions of the residual stresses and plastic strains. In the proposed approach, the spatial information of force versus time from the DEM simulation is utilized in the FE Model to solve the shot peening problem as a transient problem. The results show that the RCS distribution obtained closely matches with that of the com∗Corresponding author. Address: GE India Technology Center,122, EPIP,Whitefield Road, Bangalore-560066, ph: +919980017207, fax:+918028413113 Email addresses: [email protected] (Baskaran Bhuvaraghan), [email protected] (Sivakumar M.Srinivasan), [email protected] (Bob Maffeo), [email protected] (Robert D McCLain), [email protected] (Yogesh Potdar), [email protected] (Om Prakash) Preprint submitted to Advances in Engineering Software May 22, 2010 putationally intensive direct FEM simulation. It has also been established, in this paper, that this method works well even in the situations where the robust unit cell approaches are found to be difficult to handle.