微细多次切割电极丝振动模型的验证

Vibration Model Validation for Multi-cutting Wire Electrode in WEDM

针对因微米级切缝充满工作液,且放电间隙温度极高因素,线切割电极丝振动模型很难通过实验直接验证的难题,根据S.Y.Modarres等人[1]用Hamilton原理建立且已验证的轴向流中两端简支圆柱体振动模型,结合细小电极丝在放电加工时处于张紧状态特点,首先,忽略S.Y.Modarres等人模型中的轴向振动项,简化轴向流体中的摩擦阻尼系数;然后,考虑电极丝平面振动而引起的轴向附加力,以及电极丝横向脉冲放电合力等因素,演变得出的数学模型和文献[2]用Newton第二定律建立的多次切割电极丝流固耦合非线性平面振动模型完全一致,从而验证文献中[2]推导的多次切割电极丝振动数学模型合理性。为分析电极丝动态特性,解决目前微细多次切割精度不高,稳定性较差问题,提供基础理论依据。

It is very difficult that vibration model for multi-cutting wire electrode in WEDM to be validated because of micron kerf with working fluid and extreme temperature in discharge gap.The purpose of this paper is to validate vibration model for multi-cutting wire electrode in WEDM.First,based on the vibration model of simple support cylinder at both ends which has be established using Hamilton’s principle and validated by S.Y.Modarres et al[1],and combined with machining characteristics of fine wire electrode be tensed during machining process,the axial vibration item in S.Y.Modarres’s vibration model is ignored,the friction damping factor in axial flow is be simplified.Then,considering the axial additional force caused by wire electrode plane vibration and the resultant force caused by impulsive discharge in horizontal direction,the mathematical model evolved from S.Y.Modarres’s vibration model is same with the fluid-solid coupling nonlinear plane vibration model of multi-cutting wire electrode which is established by Newton’s second law in literature[2].Thus it is concluded that vibration model of multicutting wire electrode in the literature[2]is reasonable,which provide basic theory for solving the poor accuracy stability in WEDM.