本文针对常规铣削加工大批量移除高温合金时，加工效率低、刀具磨损严重和加工成本高等问题，提出机械-液体耦合断弧的运动短电弧铣削加工高温合金的新方法。自主开发了运动短电弧铣削加工的实验装置，借助该平台深入研究加工过程中的材料移除机制，着力解决运动短电弧铣削加工高温合金材料时，加工效率低和加工质量差的问题。本文根据脉冲电源输出的电弧铣削加工中放电率低的问题，提出了基于大功率直流电源供电的机械-液体耦合断弧的运动短电弧铣削加工方法。通过实验发现借助管状工具电极的高速旋转和内部高压冲液的机械-液体耦合作用，实现了稳定的断弧并有效提升电弧铣削加工中的放电率。在此基础上设计并搭建了一套运动短电弧铣削加工实验平台。借助有限元仿真软件研究了极间放电间隙内冲刷液体的流速，并建立了电弧几何模型和热源模型，通过FLUENT仿真了冲刷液体移除熔融态金属的蚀除过程。最终，基于仿真和实验研究，建立了运动短电弧加工机理模型。加工效率和加工精度是运动短电弧铣削加工的重要研究内容。本文重点研究了不同加工参数对工件材料移除效率和工具电极损耗的影响。提出在运动短电弧铣削加工中引入辅助冲液，以进一步提升工件材料的加工效率。针对运动短电弧铣削加工电极损耗严重的问题，采用响应面法进行工艺参数优化，并得到满足优化目标的最优加工参数组合。在此基础上，提出并建立了运动短电弧铣削加工单道和平面的电极损耗补偿模型，并通过实验验证了模型的有效性。分析了运动短电弧铣削加工的表面形貌和重铸层形成特征，对不同加工参数下的加工表面完整性进行了系统研究。采用灰理论中得灰色关联分析方法，建立了灰色关联度矩阵，依据该矩阵开展了不同加工参数对表面粗糙度和重铸层厚度影响程度的分析。之后，针对运动短电弧铣削加工表面完整性的工艺参数优化这一多目标决策问题，采用灰局势决策理论模型和方法，给出了局势效果样本并建立了统一测度空间基础上的满意局势，得到了最优的表面完整性的工艺参数组合。
Aiming at the problems of low processing efficiency, severe tool wear and high processing cost when removing large quantities of superalloys by conventional milling, this paper proposed a new method of moving short arc milling by mechanical-liquid coupling arc breaking. Independently designed and built an experimental platform for moving short arc milling, in-depth studied the material removal mechanisms of moving short arc milling, and focused on solving the problems of low processing efficiency and poor quality when high temperature alloy materials are processed.In this paper, according to the problem of low discharge rate in arc milling machining by pulse power supply, a motion short arc milling machining method based on mechanical-liquid coupling arc interruption powered by high-power DC power supply is proposed. It was found that with the high-speed rotation of the tubular tool electrode and the mechanical-liquid coupling effect of the internal high-pressure flushing liquid, a stable arc interruption was achieved and the discharge rate in arc milling was effectively improved in experiments. On this basis, a set of experimental platform for moving short arc milling machining was designed and built. With the help of finite element simulation software, the flow velocity of the flushing liquid in the electrode discharge gap was studied, and the arc geometry model and heat source model were established. The erosion process of the flushing liquid to remove molten metal was simulated by FLUENT. Finally, a mechanism model of short arc machining was established based on simulation and experimental research.Machining efficiency and machining accuracy are important research contents for moving short arc milling. This paper focused on the effects of different processing parameters on the removal efficiency of workpiece materials and tool electrode wear. It is proposed to further improve the machining efficiency of the workpiece material with the help of auxiliary flushing in the moving short arc milling process. Aiming at the problem of severe electrode loss caused by moving short arc milling, the response surface method was used to optimize the process parameters, and the optimal machining parameter combination that met the optimization goal was obtained. On this basis, an electrode loss compensation model for single pass and plane machining by moving short arc milling was carried on. Then the the model effectiveness was verified by experiments.The surface morphology and the characteristics of the re-solidified layer were analyzed in moving short arc milling, and the machining surface integrity under different machining parameters was systematically studied. Using the gray correlation analysis method obtained in the gray theory, a gray correlation matrix was established, and the degree of influence of different machining parameters on the surface roughness and the thickness of the re-solidified layer was analyzed. Finally, for the multi-objective decision-making problem of process parameter optimization of the surface integrity of moving short arc milling, the gray situation decision-making theoretical model and method were used to give a situation effect sample and established a satisfactory situation based on a unified measurement space. Finally, the optimal combination of process parameters for surface integrity were obtained.
