【作者】 胡玉景；

【导师】 张建华；

【作者基本信息】 山东大学 ， 机械制造及其自动化， 2006， 博士

【摘要】 硬脆材料常用的加工方法很多，但现有加工方法各有利弊。超硬脆材料的难加工性制约了其推广应用。本文查阅了大量的相关文献，结合当前常用的加工方法，在已有研究成果的基础上提出了超声振动-磨削-脉冲放电复合加工技术及其智能控制的研究课题，对复合加工的加工机理、复合加工控制系统的硬件结构、加工智能控制系统的构建、加工参数的优化选择、复合加工工艺数据库的设计实现及在Window 2000环境下系统软件的实现等进行了深入系统地研究。 本文通过建立复合加工过程的物理模型对复合加工的加工机理进行了深入系统的分析，指出在复合加工过程中放电加工、磨削加工和超声波加工互为有利条件，放电加工产生的表面变质层和表面拉应力有利于磨削加工和超声波加工的材料去除，磨削加工和超声波加工生成的新鲜表面为下一次脉冲放电做好准备。超声振动产生的空化作用、泵吸作用和涡流作用提高脉冲放电加工和磨削加工的效率；超声振动改变了磨粒的运动路径，从而减小了磨削力和磨削加工的有效加工时间，在加工区域产生明显的应力和能量传递集中现象，减少材料内部微观裂纹和表面破碎的产生。 研制开发了一套超声振动-磨削-脉冲放电复合加工数控机床，详细介绍了数控机床关键性部件主轴和超声振动系统设计，采用高精度旋转集流环解决了工具电极的超声振动信号输入问题，采用高精度花岗石套解决工具电极的旋转精度问题。实现了磨削加工、超声波加工和电火花加工及其复合加工。 详细分析阐述了数控系统各部分的功能和工作原理，并给出了具体的实现过程。在超声振动-磨削-脉冲放电复合加工数控系统的研究基础上，建立了复合加工过程数控系统的总体架构，系统硬件采用了工控PC+NC组成的主从分布式多CPU控制模式，以工控PC为上位机，实现后台任务管理；PMAC-Ⅰ型运动控制器、脉冲电源CPU和超声电源CPU作为下位机实现加工过程的前台处理任务。 试验确定了复合加工各参数对加工工艺效果的影响曲线，采用神经网络技术更多还原

【Abstract】 Many machining methods are used in the production of hard-brittle material. However, all have both advantages and disadvantages. Hard machinability of hard-brittle material is crucial for its application. On the basis of analyzing the present situation of production of hard-brittle material at home and aboard meanwhile studying abundant references, this dissertation presents research on combined machining of ultrasonic vibration assisted grinding and electrical discharge machining mechanism and its intelligent control. Combined machining mechanism, design of machine tool structure, hardware structure of control system basing on PC, intelligent selection and prediction of parameters, structure and algorithm of fuzzy neural network controller, design and realization of technology database and realization of software system in the windows 2000 environment were discussed systematically and thoroughly in this dissertation. Combined machining mechanism was analyzed systematically based on development of comnbined machining model and machining mechanisms of each process. Point out that ultrasonic vibration machining, grinding and electrical discharge machining benefit each other in combined machining; finish surface of EDM was helpful to MRR of grinding and ultrasonic vibration machining; and fresh suface produced by grinding and ultrasonic vibration machining was prepared for next pulse discharge; ultrasonic cavitation, pump-absorption and bow wave effect were helpful to liquid circulation, and could improve the stability and accuracy of the machining process; ultrasonic vibration altered the path of grinding, reduced grinding force and effective machining time, which could decrease the produce of micro-crack.The machine tool for combined machining was developed. The crucial parts, principal axis and ultrasonic vibrating unit, were designed in details. Collecting ring was introduced to realize inputting of ultrasonic signal and rotating of principal axis. Two granite jackets could realize high-precision rotating orientation of principal axis. Function and realization of every module were described in details. Hardware system of更多还原