Stress Intensity & SCF Investigation with degree of Cold Expansion Effect in AL7495 Plate with Hole

Abstract

The cold expansion has been one of the important manufacturing technologies for lightweight and durable components in most industries It is a proven versatile method for fatigue life improvement in plates with holes subjected to loading. Finite element analysis of residual stresses on such a plate helps in finding failure parameters and keeping a record of them. In this paper, stress intensity and stress concentration factors (SCFs) are analyzed for varying degrees of cold expansion (DCE) up to 6%. To study three-dimensional stress concentration factors, binomial functions are utilized analytically for varying DCE. Stress concentration at the plate surface and midplane was analyzed carefully as buckling effects may coincide. Also, stress intensity is analyzed for variation of DCE, which may lead to crack initiation as materials yield due to excessive compressive stress or deformation. A new approach by varying the thickness and the properties of the material at the entry face and at the exit face was adopted. It is observed that the tangential residual stress occurs at the midplane of the hole edge.