A method of modeling residual stress distribution in turning for different materials

This paper introduces a more comprehensive experimental model which has the capability of predicting residual stress profile. The main advantage of this model over the existing models that it provides the effect of machining parameters on maximum residual stress and determines both the location and depth of this maximum residual stress. Five different materials namely; stainless steel-304, steel-37, 7001 and 2024-aluminum alloys and brass were machined by turning utilizing one of experimental design techniques based on response surface methodology. Tensile strength of these materials and both cutting speed and feed rates are considered as three input parameters affecting residual stress distribution. The residual stress distribution in the machined surface region was determined using a deflection-etching technique. It is proposed here that the residual stress profile is a deterministic function of the three input parameters used. Also, it is postulated that the residual stress profile along the depth beneath surface is a polynomial function of the depth beneath surface and the coefficients of this polynomial are, in turn, functions of the input parameters. The model has been developed and has been checked for accuracy. (C) 2002 Elsevier Science Ltd. All rights reserved.