放电位置随机分布的电火花线切割加工仿真模型

Simulation Model of WEDM with Random Distribution of Discharge Position

在电火花线切割单脉冲放电过程仿真的基础上,基于有限元软件ANSYS提出了一种放电位置随机分布的电火花线切割加工温度场仿真模型。在仿真过程中,放电位置随机分布,并引入"生死单元技术"去除高温蚀除的单元,得到了线切割连续脉冲放电加工过程的表面效果。然后利用温度场仿真结果计算不同放电参数下的材料去除率,并基于脉冲利用率和电极丝换向时间进行修正,发现修正后材料去除率仿真结果与实际加工结果之间误差小于10%,验证了电火花线切割加工连续脉冲随机放电的仿真模型的准确性。其中,电火花线切割加工过程的脉冲利用率、电极丝换向时间是导致仿真结果出现偏差的主要因素。为了分析实际加工过程的脉冲利用率,搭建了脉冲利用率检测装置,对不同伺服条件下的脉冲利用率进行了统计。

Based on the simulation of single-pulse discharge process of WEDM, a simulation model of temperature field of WEDM with random distribution of discharge position is proposed based on finite element software ANSYS. In the simulation process, the discharge position is randomly distributed, and the "life and death unit technique" is introduced to obtain the erosion effect of the continuous discharge process of the WEDM. Then the temperature field's simulation results are used and the material removal rate under different discharge parameters is calculated. Based on the pulse utilization rate and the wire reversal time, it is found that the error between the modified material removal rate simulation result and the actual machining result is less than 10%, and the accuracy of the continuous pulse random discharge simulation model of WEDM is verified. Among them, the pulse utilization rate and the wire reversal time of the WEDM process are the main factors leading to the deviation of the simulation results. In order to analyze the pulse utilization rate of the actual machining process, a pulse utilization rate's detection device was built to calculate the pulse utilization rate under different servo conditions.