面向流屑角突变建模的切削状态参数经验公式的获得及应用

从提高流屑角突变模型的预测精度出发,建立了切削状态参数与3个切削控制参数之间关系的新经验公式。提出了一种通过迭代法准确设定有限元仿真软件刀-屑摩擦因数的方法,并通过直角切削Al6061-T6工件的有限元仿真试验,获得了一组不同切削控制参数组合条件下的切削状态参数数据。根据该数据拟合出剪切角φ、刀-屑摩擦角β、剪切应力τs关于刀具前角γ0、进给量f和切削速度v的经验公式,并通过一组直角切削试验,验证了所得经验公式的有效性。将新建经验公式应用于流屑角突变建模过程后,所得模型关于突变临界切削宽度的平均预测误差减小了27.2%。

Obtaining and Applying of Empirical Formulas of Cutting State Parameters for Modeling of Chip Flow Angle Catastrophe

To improve the prediction accuracy of the model of CFA catastrophe,the empirical formulas between CSP and three cutting control parameters are established.A method of accurately setting the friction coefficient in the finite element simulation software by iteration is proposed,and a set of CSP changing with the cutting conditions are obtained through the finite element simulation of the orthogonal-cutting of Al6061-T6 workpiece.The empirical formulas for calculating the CSP(the shear angleφ,the tool-chip friction angleβand the shear stressτs)are fitted accordingly,in which the tool rake angleγ0,the feed rate f and the cutting speed v are considered.A series of orthogonal-cutting experiments of Al6061-T6 workpiece are completed to validate the accuracy of these empirical formulas.After applying the new empirical formulas to the modeling of CFA catastrophe,the average of prediction error of the critical width of cut of the new model is reduced by 27.2%compared with the empirical formulas established by previous researchers.