Engineering Residual Stress into the Workpiece through the Design of Machining Process Parameters

Abstract

The surface integrity of a machined component that meets the demands of a specific application requirement is defined by several characteristics. The residual stress profile into the component is often considered as the critical characteristics as it carries a direct effect on the fatigue life of a machined component. A significant amount of effort has been dedicated by researchers to predict post process stress in a workpiece using analytical, experimental, and numerical modeling methods. Nonetheless, no methodology is available that can express the cutting process parameters and tool geometry parameters as functions of machined residual stress profile to allow process planning in achieving desired residual stress profile. This research seeks to fill that void by developing a novel approach to enable the extraction of cutting process and tool geometry parameters from a desired or required residual stress profile. More specifically, the model consists in determining the depth of cut, the tool edge radius and the cutting forces needed to obtain a prescribed residual stress profile for an orthogonal machining operation. The model is based on the inverse solution of a physics-based modeling approach of the orthogonal machining operation and the inverse solution of the residual stress prediction from Hertzian stresses. Experimental and modeling data are used to validate the developed model. The work constitutes a novel approach in engineering residual stress in a machined component.