Study of Strain and Residual Stress Distribution in the Thickness Direction by Layer Removal Method and X-Ray Diffraction

Investigation of strain and residual stress in materials plays an important role in evaluation of the lifetime of machine components. Various methods have been also developed to determine the strains and residual stresses. X-ray diffraction is often used technique to measure the residual stress in the surface material, while layer removal method is common applied to determine the in-depth residual stress distribution. This paper will present the technique combining the X-ray diffraction with layer removal method to study of the strain and residual stress distribution in the thickness direction on JIS S45C quenched specimen. The result of the strain and residual stress distribution through the thickness direction are determined, in which the residual stress distribution is the inhomogeneous.

I. Introduction

Residual stresses are induced during almost manufacturing processes such as plastic deformation, machining or heat treatment process [3]–[7]. Residual stresses are one of important factors affecting to the stability, fatigue life and corrossion resistance of machine components. For instance, the fatigue life of parts can be improved when the surface of parts has compressive residual stress, in the other hand tensile resiual stress in the surface of parts will reduce the fatigue life of parts and even cause damage of parts [4]–[6]. Therefore, determination of the residual stress plays significant role in improvement process of the working quality of machine components.