1. Introduction
As an important branch of advanced manufacturing technology, special machining technology, especially EDM technology, has become an indispensable part of advanced manufacturing technology field after more than half a century of development since its inception in 1940s. Especially after entering the 1990s, with the development of information technology, network technology, aviation and aerospace technology, material science and technology and other high-tech development, EDM technology is also developing in a deeper and higher level. Although some traditional machining technologies have shown the advantages of high processing efficiency in some difficult to machine materials (especially in the field of mold processing) through their own continuous development and integration with other related technologies, the application of these technologies does not and can not completely replace the EDM Technology in the processing of difficult to machine materials, complex surfaces, molds and other fields Status. On the contrary, by learning from the development experience of other processing technologies, EDM technology is developing to the direction of micro refinement, high efficiency, precision, automation, intelligence and so on.
2. Development status of EDM Technology
At present, due to the complexity and randomness of the discharge process and the lack of innovation in research methods, no breakthrough has been made in the field of EDM basic theory research. However, in the field of processing technology and control theory research, because the research results can be directly applied to production practice, it has become a more active field in the research of EDM technology. The research focuses mainly focus on high efficiency machining technology, high precision machining technology (such as mirror processing technology), low loss processing technology, micro processing technology, non-conductive material processing technology In addition, the technology of EDM surface treatment, intelligent control technology (such as artificial neural network technology, fuzzy control technology, expert system, etc.) and operation safety, environmental protection and so on. In terms of process equipment development, the current new EDM machine tools have been comprehensively improved in terms of processing function, machining accuracy, automation and reliability. Many machine tools have the functions of online detection, intelligent control and modularization. They are no longer traditional special machining machines, but more like CNC machines or even machining centers in cutting.
3. The development trend of EDM technology
With the rapid development of advanced manufacturing technology and the aggravation of market competition in manufacturing industry, higher requirements are put forward for EDM technology. At the same time, it also provides a new impetus for the research of EDM machining theory, process development and equipment update. In the future, the machining objects of EDM should mainly face the difficult to machine materials and complex surfaces which are difficult to be realized by traditional machining. Among them, fine machining, precision machining, narrow groove machining and deep cavity machining will become the development focus. At the same time, we should pay attention to the composite application of other special machining technology or traditional cutting technology, give full play to the advantages of various processing methods in the processing of difficult to machine materials, and achieve joint value-added effect. Compared with the cutting technology, EDM technology is still a relatively young technology. Therefore, in the future development, we should learn from the experience and achievements obtained in the development of cutting technology, according to the technical characteristics of EDM, select appropriate machining theory, control principle and process method, and constantly improve on the basis of existing achievements Innovation. The development trend of EDM machine tools towards numerical control is irreversible, but we should not blindly pursue "large and complete", and should be market-oriented and establish an open CNC system. Generally speaking, the development trend of EDM Technology in the future should be high efficiency, high precision, low loss, microminiaturization, automation, safety, environmental protection and so on.
3. Development trend of EDM theory
In recent years, the basic theoretical research of EDM has not made substantial progress. Although some scholars have put forward some new views on the discharge trace and material erosion principle in the machining process, no significant breakthrough has been made in the research of EDM mechanism. The active research fields mainly focus on processing technology theory and control theory.
In the theoretical research of machining technology, the research focus is how to improve the surface quality and processing speed of EDM, reduce the loss, expand the scope of EDM, and explore the machining methods of complex and micro structure. By applying the research results to production practice, the machining performance of EDM has been improved. In the aspect of control theory research, intelligent control has always been the research focus. Most of the new EDM machine tools produced at home and abroad adopt intelligent control technology. The application of this technology makes the operation of machine tools easier and requires lower requirements for operators. At the same time, the intelligent control system has the ability of self-learning, which can automatically monitor and adjust the processing process online to realize the optimal control of the processing process.
