Residual stress and distortion in samples of complex geometry subjected to spray quenching

Abstract

Paper presented at the 9th International Conference on Heat Transfer, Fluid Mechanics and Thermodynamics, Malta, 16-18 July, 2012.This paper discusses the residual deformation modelling of a complex shaped stainless steel AISI316L component heated to 900C and quenched with a water spray subcooled to 80K. The paper shows that accurate deformation modelling of the problem necessitates not only an adequate mathematical formulation of the physical system but also the application of precise thermal and mechanical boundary conditions. Correlations of experimentally measured spatio-temporal heat transfer coefficients found valid for spray Reynolds numbers, Res  Gdd  f , of 6×10-2 < Re < 3 and spray Weber numbers, 2 s d f We  G d   , of 4.6×10-7 < We < 4.1×10-2 used in the calculation are presented. These boundary conditions are used in a finite element model (FEM) to enable predictions of the deformation history of a complex geometry subjected to spray quenching. The results of the modelling are compared to the deformed shape of the processed component. The excellent agreement between the modelling and experiment suggest that the method used to analyse this problem is consistent and may be applied to determine the residual stress and strain formation of complex shaped components subjected to a spray quench with great accuracy. The results of this study provide the opportunity to do life assessments with reliable residual stress and strain predictions which may be applied to components such as electronic chips, aluminium extrusions or metal sheet rollers.