一种快速有效的薄壁件加工表面误差预测算法

 在切削力作用下，刀具/工件的变形是影响薄壁弱刚度件加工精度与质量的关键因素，快速有效地进行表面误差的预测是实现工艺参数优化及在线刀具路径补偿的前提。针对立铣加工过程，提出了一种考虑刀具/工件变形位置的快速柔性迭代算法，基于此建立了薄壁件加工变形预测的有限元计算模型，并通过等效集中力作用位置的确定、模型分割及最小化网格重划方法进一步提高了模型的计算速度。通过刀具/工件的瞬时接触区域的限定算法、实际切深的修正算法、材料去除效应的模拟等关键技术更提高了模型的计算精度。以典型航空铝合金材料为对象，合理安排试验，并通过数值计算结果和试验数据的对比，表明该方法计算精度高，计算速度较文献方法提高了近2倍。

An Efficient Algorithm for Calculations of Surface Errors in Peripheral Milling

Cutting deformation is the key factor influencing the precision and quality of the machined thin-walled workpiece,and the form error prediction is the precondition for process optimization and error compensation.Cutting forces are analyzed and cutting-force model for thin-walled workpiece machining is developed,then a finite-element model is presented to analyze the surface dimensional errors in peripheral milling of aerospace thin-walled workpieces.The efficient flexible iterative algorithm is proposed to calculate the deflections as contrasted with the rigid iterative algorithm used in the literatures.Meanwhile,some crucial techniques such as the finite-element modeling of the tool-workpiece system;the determinant algorithm to judge instantaneous immersion boundaries between the cutter element and the workpiece,the iterative scheme for the calculations of tool-workpiece deflections considering the former convergence cutting position,are studied.The proposed approach is validated and proved to be efficient through comparing the obtained numerical results with the test ones.