Influence and optimization criterion of milling modes and process parameters on residual stress

摘要

The reduction and control of residual stress is very important to improve the surface quality and machining accuracy of the parts. In this paper, in order to reveal the effects of different milling modes and process parameters on the residual stress, the aluminum alloy Al7050-T7451 is used as the machining object and the finite element simulation software AdvantEdge is applied in establishing the milling model. It is found that up-milling is better than down-milling in low-speed and there is no obvious difference between them in high-speed. Besides, high-speed machining can obtain the smaller depth of sub-surface residual stress. Compared with low-speed, high-speed is more advantageous to realize the unification of quality and efficiency. What's more, decreasing cutting width and improving cutting depth is easy to obtain ideal residual stress when the material removal rate is constant. Experiments on up-milling and down-milling have verified the validity of the finite element model and the effects of milling modes and process parameters on the residual stress. It has laid a solid theoretical and practical basis for constructing process optimization criteria, choosing appropriate milling modes and optimizing process parameters.