车铣复合加工过程阻尼与切削稳定性研究

Study on Process Damping and Cutting Stability in Combined Turn-milling Machining

车铣复合加工具有一次装夹多工序加工、加工表面温度低及刀具磨损小等优势,非常适用于起落架等复杂回转类零件的加工。加工稳定性分析是进行参数优选、避免加工颤振的有效方法,在低速车铣复合加工过程中,过程阻尼会对稳定性边界产生显著影响。本文中分析了车铣复合加工过程阻尼的产生机理,建立了等效过程阻尼模型;在车铣复合加工动力学方程中引入过程阻尼,实现了考虑过程阻尼的车铣复合加工稳定性预测,得到低速切削区域的精确稳定性边界;并分析了过程阻尼对稳定性边界的影响规律,最后利用车铣加工切削实验验证了本文提出的考虑过程阻尼的稳定性预测模型的正确性。研究结果表明,过程阻尼会提高稳定性边界,且随着切削速度的降低提升作用愈发明显。

The turn-milling combined machining has the advantages of one-time multi-step machining,low surface temperature and small tool wear,which is very suitable for machining complex rotary parts such as landing gear.Machining stability analysis is an effective method to optimize parameters and avoid machining flutter.In low-speed turn-milling combined process,process damping has a significant influence on stability boundary.In this paper,the mechanism of damping in the turn-milling machining is analyzed.The equivalent process damping model is established.The process damping is introduced into the dynamic equation of turn-milling.The stability prediction in turn-milling combined machining considering process damping is realized.The precise stability boundary of the cutting area is analyzed,and the influence of the process damping on the stability boundary is analyzed.Finally,the prediction model for stability considering the process damping is verified by using the milling experiment.The results show that the process damping will increase the stability boundary,and the effect will increase as the cutting speed decreases.