薄壁板高速铣削加工过程中的让刀误差预测

Milling error prediction of thin-walled parts during high-speed machining

为了研究薄壁工件在铣削加工过程中的让刀误差以及获得使让刀误差较小的优化铣削参数,以薄壁板为例,在进行高温拉伸试验和高速压缩试验获得材料力学性能的基础上,建立了薄壁板铣削过程的热力耦合有限元模型.通过模拟螺旋立铣刀与工件材料之间相互的物理作用,获得了铣削力的变化曲线和铣削热的分布,同时得到了在刀具与工件之间物理作用下壁板随刀具的旋转与进给运动而产生的让刀变形,从而得到了薄壁板在铣削过程中的最大让刀误差.根据该有限元模型的结果可以优选薄壁件铣削用量,优化刀具几何形状,弥补让刀变形.

To study milling error and optimize machining parameters that minimize the deflection during cutting low rigidity part, a thin walled panel was taken as an example. A new finite element model （FEM） suitable for dynamic machining error prediction of low rigidity components was presented. Depending on high speed impact experiment and material drawing experiment, the constitutive model of A17050T7451 was achieved under machining conditions when high strain rate, high strain and high temperature occur. The achieved workpiece material constitutive model was put into the finite element model to simulate thermo-mechanical coupling, dynamic behavior and cutting mechanics which occurred in the machining process of the thin-walled structure. Milling error was obtained during the rotation and feed movement of the tool. The simulation model presented is helpful for determining the cutting parameters, geometric accuracy and tool geometry without performing real cutting experiments for rapid machining of complex low-rigldity parts.