ABSTRACT

In barrel finishing, the grinding fluid as a liquid processing medium has an important effect on aluminum alloy parts finishing. Therefore, the wettability of grinding fluid by contact angle and quantum chemical calculation was analyzed. Based on different grinding fluid, the experiments on barrel finishing were achieved. And, the effect of barrel finishing on plastic deformation and residual stress of aluminum alloy were discussed utilizing electron backscattered diffraction (EBSD) and X-ray diffraction (XRD). The results show that hydrogen peroxide and triethanolamine oleate can enhance the wettability of grinding fluid. The A3 grinding fluid with good wettability can obtain the best surface roughness and brightness. The main depth influence range of plastic deformation and residual stress is at 0~200 μm from the upper surface of the workpiece, which indicates that barrel finishing has the effect of low-stress plastic deformation. And the material removal mechanism of low-stress plastic deformation in barrel finishing is proposed. It shows that barrel finishing can not only meet the requirements of good surface roughness, but also restrict the formation of subsurface damage due to the low-stress plastic deformation.

摘要

在滚筒精加工中，磨削液作为液态加工介质，对铝合金零件的精加工有着重要的影响。因此，通过接触角和量子化学计算分析了磨削液的润湿性。针对不同的磨削液，进行了滚筒精加工实验。并且，利用电子背散射衍射（EBSD）和X射线衍射（XRD）讨论了滚筒精加工对铝合金塑性变形和残余应力的影响。结果表明，过氧化氢和油酸三乙醇胺能提高磨削液的润湿性。润湿性好的A3研磨液可以获得最佳的表面粗糙度和亮度。塑性变形和残余应力的主要深度影响范围为距工件上表面0~200 μm，这表明筒体精加工具有低应力塑性变形的效果。并提出了机筒精加工低应力塑性变形的材料去除机理。结果表明，滚桶精加工不仅能满足良好的表面粗糙度要求，而且能抑制低应力塑性变形造成的亚表面损伤的形成。