Prediction of Surface Residual Stress on Titanium Alloy generated by Belt Grinding using Molecular System Dynamics

Abstract

Abstract With the reason of its high strength, good corrosion resistance and high heat resistance, titanium alloy has been widely used in aeronautical field, especially in aero-engine design. Because of the characteristics of cold state and flexibility, belt grinding is one of the effective titanium alloy finishing. However, the variation of residual stress with grinding parameters in the belt grinding process are not clear, which greatly limits the further application of this method. In this paper, based on the knowledge of molecular system dynamics, a molecular system dynamics model of residual stress on the surface of abrasive belt grinding of titanium alloy is established. Based on the corresponding intermolecular potential function of titanium alloy material, a linear regression equation is established, and the expression of residual stress at molecular level on the surface of belt ground titanium alloy was obtained. The model is simulated with MATLAB, and the results are in good agreement with the intermolecular potential model. Through relevant experiments, the experimental results are compared with the simulation results of titanium alloy molecular system, the error is analyzed and the conclusion is given. When the grinding linear velocity is 8-24 m/s and the feed velocity is 20-60 m/ min, the residual stress of TC17 alloy belt grinding is - 169 to – 254 MPa, and the model prediction error is within 20%.