中文摘要：

微细电火花加工技术因其非接触加工等显著特点，在难加工合金材料微细制造领域具有突出的优势与潜力．选择对加工性能影响较大的峰值电流、脉宽、脉间及电容4种电参数，开展了难加工合金微细通道电火花加工正交实验，并结合实验结果分析了电参数对加工时间和电极损耗的影响规律．最后，针对两个加工目标，采用多目标优化算法得到了最优电参数组合，并分别在不锈钢、殷钢、钛合金3种难加工合金材料上加工了微细通道．实验结果表明，放电参数对加工时间和加工效率具有显著影响，采用所提出的多目标优化方法可以在保证加工质量的同时有效提高加工效率．

英文摘要：

Due to its contact-less process, micro-electrical discharge machining （EDM） enables very small machining forces between the electrode and workpiece, and it has been one of the most important technologies in micro-manufacturing field of difficult-to-cut alloy materials. Discharge peak current （I）, pulse duration （ To. ）, pulse interval （Toff） and capacitance （C） are selected as experimental parameters, and an orthogonal experiment of micro-channels on difficult-to-cut alloy materials is carried out. Moreover, the machining characteristics of the electrical parameters on machining time and electrode wear are analyzed according to the results of experiments. Finally, a multi-objective optimization method is employed to achieve the highest processing efficiency and the lowest electrode wear, and micro-channels on the three kinds of difficult-to-cut materials, stainless steel, invar steel, titanium alloy, are machined with the optimal parameters. The experimental results show that the electrical parameters have a great impact on processing efficiency and quality, and the processing efficiency can be improved greatly without losing machining quality by the proposed multi- objective optimization method.