Study on control of the three-dimensional shape and the function of the magnet by a local pulse energy input machining

由于磁力的作用，用车削、铣削、磨削等传统加工方法难以加工出永磁体。然而，电火花加工已被用于磁性材料的形状加工。本研究阐明了电火花加工永磁体深度方向的磁通密度与温度分布的关系。测量了加工钕磁铁的磁通密度。结果表明，磁体内部的平均温度取决于输入能量，取决于放电条件。电火花加工后表面磁通密度的减小受面积大小的影响，而减小的幅度则与磁体内部温度的升高有关。因此，它不是由简单输入能量的大小决定的。

It is difficult to machine permanent magnets by traditional machining such as turning, milling and grinding, because of magnetic force. However, EDM has been used for shape machining of magnetic materials.In this study, to clarify the relationship between magnetic flux density and temperature distributions in depth direction of permanent magnet by EDM. The magnetic flux density of a machined neodymium magnet was measured. The results showed that the average temperature inside of the magnet is determined by the input energy, depending on the discharge conditions. A decrease of surface magnetic flux density after EDM is affected by the magnitude of the area and the amount of decrease is due to the increase of the internal temperature of the magnet. Therefore, it isn't determined by the magnetude of the simply input energy.