基于Simulink反馈方法的钛合金铣削刀具磨损预测

A Novel Method for Tool Wear Prediction in Titanium Milling by Simulink Feedback Method

钛合金因其突出的综合性能广泛应用于航空航天领域,然而由于其难加工性,在钛合金切削过程中极易产生刀具磨损,所带来的加工精度低、表面质量差等现象严重影响钛合金的切削效率及经济效益。因此建立合理的钛合金铣削磨损模型对实际加工生产具有重大的指导意义。考虑了实际切削加工过程中的热力耦合条件,基于磨粒、黏结、扩散三种磨损机理,结合磨损过程铣削刀具的几何形状改变,利用Simulink软件进行反馈仿真预测,获得后刀面磨损带曲线;并通过实际铣削试验进行刀具寿命试验,对仿真模型的可靠性进行验证。结果表明,该方法可以较好地预测刀具后刀面磨损带长度随时间的变化,整体预测误差在22%以下。该研究提高了刀具磨损带的计算精度,并为切削参数的合理选择提供理论基础。

Titanium alloy Ti6Al4V is widely used in the aviation and aerospace industry.However,this material is typically difficult-to-machine due to its intrinsic characteristics,such as poor thermal conductivity,high strength at elevated temperature,etc.A novel method is proposed to predict tool wear in machining of the titanium alloy.In this method,a thermo-mechanically-coupled tool wear model,consisting of abrasion,adhesion and diffusion mechanisms,is implemented in the Simulink software.The geometric features of a worn-tool are updated at different wear stages in the simulation.Tool wear prediction is conducted and validated by milling experiments under various milling conditions.The results show that the proposed method can well predict the extent of the tool flank wear,and the relative error between the experimental and the prediction results is within 22%.This study offers a guidance to the determination of tool life and optimization of process parameters in a machining process.