Home-made pulse magnet power supply for magnetizing permanent magnets and magnetic measurements

Abstract

In this article, we propose a home-made pulse magnetic field generation system constructed using a thyristor and large capacitance capacitors to generate high magnetic fields to investigate magnetic properties and magnetize the magnet and high-performance magnetic materials at room temperature. The proposed system produced a magnetic induction (magnetic field) μ 0H of 15.6 T with the 33.6 mF capacitor and an excitation voltage of 600 V. Further, we designed a new power supply system and a pulse magnet using the commercially available pulse magnet and power supply. We found that the duration time of the magnetic fields (t d) and the generated magnetic fields were three and four times larger than those for a conventional system, respectively. We also performed magnetization of a NEOMAX permanent magnet; the coercivity (ΒCJ) was 2.0 T, and the magnetization saturated at ~4.0 T. These results suggest that we can magnetise a permanent magnet such as NEOMAX with strong magnetic fields using this system. Further, the magnetic measurements of these magnets can be performed as well. The merit of our system is that the capacitance of the capacitor bank is larger than that of other studies or general commercial power supplies. Therefore, relatively high magnetic fields with long duration time can be generated. We also performed experiments on the magnetization process (M-H) of Gd to investigate the magnetocaloric effect in high magnetic fields. The magnetic entropy change was comparable to the result of former investigation. We believe that our research can contribute to the development of permanent magnets and magnetic materials for scientific and industrial use because our system allows the generation of strong magnetic fields at room temperature.