纵向超声辅助螺旋磨削Ti_(3)Al微孔的磨削力模型研究

Study on Grinding Force Model of Longitudinal Ultrasonic Assisted Helical Grinding Ti_(3)Al Microholes

为建立超声辅助螺旋磨孔过程中磨削力的预测模型,充分发挥磨削力在Ti_(3)Al微孔磨削工艺参数优化中的指导作用,基于切屑断面面积理论,分析了超声振动下切削变形力和摩擦力的变化,建立了超声螺旋磨孔的磨削力模型。搭建超声辅助螺旋磨削Ti_(3)Al微孔实验平台,采集磨削力数据并与所建模型进行验证。研究结果表明,磨削力随着主轴自转速度的增大而减小,并随着进给速度的增大而增大;当超声振幅由0增大至1.6μm时,平面磨削力和轴向磨削力分别减小了27.2%和28%。超声螺旋磨孔磨削力模型的预测结果与实验数据显示出良好的一致性,数值误差保持在20%以内,为超声辅助螺旋磨削Ti_(3)Al微孔的工艺参数优化提供了理论依据。

In order to establish the prediction model of grinding force in ultrasonic assisted helical grinding processes and give full play to the guiding role of grinding force in the optimization of Ti_(3)Al microhole grinding parameters,the changes of cutting deformation forces and friction forces were analyzed under ultrasonic vibrations based on the chip section area theory,and the grinding force model of ultrasonic helical grinding hole was established.The grinding force data were collected and verified with the established model by setting up an ultrasonic assisted helical grinding Ti_(3)Al microhole experimental platform.The results show that the grinding forces decrease with the increasing of spindle rotation speeds and increase with the increasing of feed speeds.When the ultrasonic amplitudes increase from 0 to 1.6μm,the surface grinding forces and axial grinding forces are decreased by 27.2%and 28%,respectively.The prediction results of ultrasonic helical grinding force model are in good agreement with the experimental data,and the numerical errors are kept within 20%,which provides a theoretical basis for the optimization of processing parameters of ultrasonic assisted helical grinding of Ti_(3)Al microholes.