Preparation and Deposition of Pr-Fe-B Permanent-Magnet Powder Using Pulsed Laser

• Published in: IEEE transactions on magnetics 2020-04, Vol.56 (4), p.1-3
• Main Authors: Nakano, M., Takeichi, S., Takashima, K., Yamashita, A., Yanai, T., Fukunaga, H.
• Format: Article
• Language: English
• Subjects: Annealing; Coating; Coercivity; Flash annealing; Iron; Magnetic properties; Magnetism; Magnetomechanical effects; Magnetometers; Mechanical properties; Permanent magnets; Perpendicular magnetic anisotropy; Powder technology; Powders; Pr–Fe–B permanent-magnet powder; Pulsed laser deposition; pulsed laser deposition (PLD); Pulsed lasers; Shafts; stainless shaft
• ISSN: 0018-9464; 1941-0069
• DOI: 10.1109/TMAG.2019.2961994

We have already prepared a thin permanent magnet with the thickness of sub-millimeter by obtaining magnet powders using a pulsed laser deposition (PLD) method. In the article, the PLD followed by a flash annealing enabled us to deposit isotropic Pr-Fe-B magnet powders with coercivity (H cj ) > 1000 kA/m on a stainless thin shaft applicable to a miniaturized motor. Observation on the surface of Pr-Fe-B magnets and evaluation on the mechanical behavior were carried out. Since the surface of a Pr-Fe-B magnet was coated by a Pr oxide through an annealing process, their magnetic properties did not degrade after one year. We also confirmed that the Pr-Fe-B magnet has the possibility to be applied to a micro-magnetization process. It was clarified that the powder technology using the PLD is useful to propose a thin magnet applicable to a next-generation small motor.