Study on Expansion of Micro-EDM Discharge Channel

为了模拟微细电火花放电通道扩展的过程,对放电等离子体通道进行了深入研究,建立了一个适用于微细电火花放电加工的等离子体扩展模型。基于介质击穿机理和磁流体力学的相关知识,模型综合考虑了等离子体扩展过程中的粘性力、表面张力及磁场箍缩力等各个作用力,使扩展过程更接近于真实。最后,通过比较微细电火花rC单脉冲放电的模型计算直径与实际加工直径,验证了等离子体扩展模型的正确性。To simulate the process of micro-EDM discharge channel expansion,discharge plasma channel has been studied.A suitable plasma expansion model of micro-EDM has been established.Based on the dielectric breakdown mechanism and relevant knowledge of MHD,the various forces such as viscous force,surface tension and magnetic pinch force,in the process of plasma expansion has been considered,which makes the expansion process closer to the real.Finally,comparing the calculation diameter of micro-EDM RC single pulse discharge model with the actual machining diameter,the correctness of plasma expansion model is verified

单氯代苯酐及其衍生物的合成方法研究进展

讨论了3（4）-氯代苯酐的主要合成方法以及它们的主要衍生物联苯二酐和二苯醚二酐等的合成方法和主要用途．综合比较了各种合成方法的利弊，并分析了这些化合物的国内外研究现状和发展趋势