Research on Influence of Milling Process Parameters on Residual Stress of 7055 Aluminum Alloy

Abstract

The residual stress induced by the process of high-speed milling is an essential factor affecting the machining deformation of structural materials. The two-dimensional modeling and numerical simulation of high-speed milling of 7055 aluminum alloy were carried out to investigate the influence of key milling process parameters on the surface residual stress of aluminum alloy, using finite element approach. Through single factor simulation experiment and multi-factor orthogonal simulation experiment, the effects of milling speed, feed rate, milling depth, milling width, rake angle and relief angle on the surface residual stress of aluminum alloy were discussed. The optimized parameter scheme was obtained by range analysis method. The results demonstrate that the surface residual stress of 7055 aluminum alloy increases with the increase of milling speed, feed per tooth and milling depth, and decreases with the increase of milling width; Using the optimized milling scheme (milling speed 2000 m / min, feed per tooth 0.1 mm / z, tool relief angle 4 °, tool rake angle 16 °, milling depth 10 mm, milling width 10 mm) could reduce the surface tensile residual stress; while using the optimized scheme (milling depth 10 mm, tool rake angle 16 °, milling width 4 mm, feed per tooth 0.5 mm / z, milling speed 4000 m / min) could reduce the surface compressive residual stress.