刀尖圆弧半径对车削颤振稳定性影响分析

Analysis of The Influence of Corner Radius on the Stability of Turning Chatter

薄壁环形工件具有尺寸大、壁厚薄、刚度低的特点,为避免车削加工时发生再生颤振影响加工精度,首先,基于工件特点建立外圆车削动力学模型并进行稳定性极限分析,通过试验获取7075铝合金薄壁件模态参数与不同刀尖圆弧半径下的车削力参数,运用数值仿真绘制出稳定性叶瓣图,对工件车削稳定性预测;其次,运用MATLAB/Simulink模块进行时域仿真,结合稳定性叶瓣图探究刀尖圆弧半径对车削稳定性的影响,验证预测的准确性。结果表明,选择稳定区域的车削参数可以有效避免车削颤振,选择较小的刀尖圆弧半径时工件的车削稳定性好,加工效率高。该项研究为铝合金薄壁环形工件车削切削参数与刀具参数的选择提供依据。

Thin-walled annular workpieces have the characteristics of large size,thin wall thickness and low rigidity.In order to avoid regenerative chatter vibration during turning and affecting the machining accuracy,firstly,based on the characteristics of workpiece cylindrical turning dynamics model is established and the stability limit analysis,through the test for 7075 aluminum alloy thin-walled modal parameters and the cutting force under different point arc radius parameters,mapped the stability lobes diagram,using the numerical simulation for predicting the stability of turning workpiece;Secondly,MATLAB/Simulink module was used for time domain simulation,and the influence of corner radius on turning stability was explored in combination with stability lobe diagram to verify the accuracy of prediction.The results show that selecting the turning parameters in the stable region can effectively avoid the turning chatter,and the turning stability of the workpiece is good and the machining efficiency is high when the smaller radius of the tool nose arc is selected.This study provides a basis for the selection of cutting parameters and tool parameters in aluminum alloy thin-wall annular workpiece turning.