超精抛光中边缘效应对材料去除量的影响

 传统环抛加工一般将工件整个包围在抛光盘内，加工之后虽然可以获得较好的工件表面，但是需耗费较多的时间，生产效率较低。针对这种情况，借助PPS快速抛光机床，依据Preston公式，对露出抛光盘的工件部分，即对所谓的边缘效应进行研究，用新的表面模型表示非线性压强分布，合理地避开了线性模型造成的压强负值问题。并且对工件材料去除量进行仿真计算，建立了新的去除模型，得出了偏心距、工件半径和抛光盘转速比值对材料去除量的影响。根据此模型，选择适当的偏心距和转速比对工件进行加工，可获得较好面型。

Edge effects on material removal amount in ultra precise polishing process

The edge effects would happen when a workpiece extends beyond a polishing tool, which could lead to low polishing efficiency. So a new skin model, representing the nonlinear pressure distribution, was proposed to avoid the negative pressure and to calculate the amount of removed materials for the case of a circular tool that polishes a circular workpiece. A material removal amount model was established considering workpiece radius, workpiece-tool center distance and speed ratio. Its simulations show that good surface figures could be achieved by choosing proper values for the latter two parameters based on that model.