中文摘要：

研究电火花单脉冲放电加工过程中的电蚀坑的温度场建模,主流的高斯热流密度分布模型只适用于较小电流参数范围内的温度场仿真,对于在大电流参数条件下,它无法准确预测电蚀坑的形貌、直径和深度。并且模型大多是采用传统的球缺计算公式去计算电蚀坑的材料去除量,与实际电火花加工过程中的材料去除情况不相符。为解决上述问题,建立了基于均匀热流分布模型的有限元模型,并运用ANSYS软件仿真电火花加工过程的温度场分布,并对传统的球缺计算公式进行了修正。同时,进行了电火花单脉冲实验,并对比分析了仿真结果与实验结果。结果表明,所建立的模型能准确地预测电蚀坑的形貌、直径和深度,采用修正后的球缺计算公式计算电蚀坑的材料去除量与实验值是吻合的,为研究电火花加工过程中电蚀坑的扩展规律提供了可靠的理论依据。

英文摘要：

Studying the temperature field distribution of discharge crater for single discharge machining in the e- lectric discharge machining （EDM） process, the widely - used Guassian heat flux distribution model is only for simu- lating the temperature field in the condition of small discharge current while it can not predict the shape, diameter and depth of the discharge crater when the discharge current is large. Moreover, those models use the calculation for- mula of spherical segment to calculate the material removal volume of discharge crater which can not match with the actual EDM process. Aiming to solve the aforementioned problem, a finite element model based on uniform heat flux distribution model is proposed and the ANSYS software is used to simulate the temperature field for single discharge EDM process. The calculation formula of spherical segment has been modified. Single spark experiments are conduc- ted and comparative study is made between the simulating results and experimental results. It indicates that the pro- posed model is able to predict shape, diameter and depth of the discharge crater accurately as well as the material re- moval volume of discharge crater which is calculated by the modified calculation formula of spherical segment which is accordance with the experimental value. Thus, this model is able to provide a reliable basis for studying the develop- ment of the melting crater during the EDM process.