Characteristics of Electrical Discharge Machining for Magnetic Material
There is difficulty in traditional machining of a permanent magnet, which is one of the functional materials, including turning, milling and grinding, because of magnetic forces. However, Electrical Discharge Machining (EDM) which is a non-contact machining method was carried out for magnet shape machining. In the EDM process, nonmagnetic materials such as cupper and graphite were typically used as electrodes to machine magnetic materials. As EDM is a thermal process, this method has the potential to control the magnetic flux density on the machined surface. In this study to clarify the influence of the magnetic flux density on the machined surface, the following machining conditions were investigated. (1)Duty Factor, (2) input energy of one pulse, (3)machined shape type. Sintered neodymium material of various sizes was used as the work-piece. The crosssection of the machined neodymium magnet was observed with a microscope for depth profiling and hardness measurement. In addition, using heat transfer analysis for single discharge, changes in magnetic characteristic were studied. The results showed that the influence of the magnetic flux density was low under low energy machining conditions. However, under high energy machining conditions or high Duty Factor, the magnetic flux density came down to a value relative to the initial value. On the other hand, the backside magnetic flux density remained approximately of the same value. From these result, the criticality of the machining conditions setup for EDM of magnetic materials has been confirmed.
EDM Permanent magnet Functional materials Heat-affected
Hideki Takezawa Tamao Muramatsu Naotake Mohri Yasushi Fukuzawa
Kogakuin University, 139 Inume-cho Hachioji-shi, Tokyo, Japan National Institution for Academic Degrees and University Evaluation, Gakuen-nishimachi Kodaira-shi, Nagaoka University of Technology, 1603-1 Kamitomioka, Nagaoka, Niigata, Japan
国际会议
The 16th International Symposium on Electromachining(第16届国际电加工会议)
上海
英文
169-173
2010-04-19（万方平台首次上网日期，不代表论文的发表时间）