基于ALE方法的钛合金超声振动车削仿真

采用ALE方法建立了钛合金超声振动车削有限元仿真模型。预测了超声振动车削过程中切削力变化规律,并将模拟获得的切削力平均值与相同条件实验获得的切削力平均值比较,验证了有限元模型的正确性。将超声振动主切削力模拟平均值与普通切削主切削力实验平均值比较,结果表明,采用超声振动辅助手段可以明显降低切削力平均值。预测了超声振动车削一个周期内工件及刀尖温度变化规律,结果表明,刀具切入阶段,工件及刀尖温度迅速升高,当刀具到达运动轨迹最大位移时,工件及刀尖温度达到最大值,随后进入分离阶段,工件及刀尖温度迅速降低。研究了超声振动振幅、频率对切削力及刀尖温度的影响规律,结果表明,随着超声振动振幅及频率的增大切削力有较明显的降低,刀尖温度有小幅降低。

Finite Element Simulation of Ultrasonic Assisted Turning of Titanium Alloy Based on ALE Method

A finite element simulation model for ultrasonic assisted turning (UAT) of Ti-6Al-4V was developed. Cutting force was predicted during one vibration period. The average simulated cutting force was compared with the experimental data with the same cutting parameters. The simulated cutting force was well agreed with the experimented one. The average simulated cutting force was compared with the experimental data in conventional turning (CT). The result shows that the average force of ultrasonic assisted turning is much smaller than the corresponding force during conventional turning. Cutting temperatures for both workpiece and cutting tool were predicted. The results indicate that a drastic increase of the maximum temperature for both workpiece and cutting tool can be observed in the initial cutting stage, and this temperature will present a swift drop after the trajectory of cutting tool reaches its maximum dislocation. The influences of frequency and amplitude were analyzed. The cutting forces increase obviously with the increase of the frequency and amplitude, and the temperature of cutting tool decrease a little with the increase of frequency and amplitude.