Enhancement in coercivity of pulse-laser-deposition-made Nd–Fe–B thick film magnets by high-speed crystallization

摘要

In order to improve the magnetic properties of Nd–Fe–B thick film magnets prepared by pulsed laser deposition, high-speed crystallization method of a pulse annealing was adopted as a postannealing process. In the case of using a Nd2.4Fe14B target, the pulse annealing under an optimum condition for the period of 1.8 s enabled us to enhance the coercivity by approximately 300 kA/m compared with the average value of samples annealed by a conventional method. The obtained sample whose composition was almost as same as the target's one had the large coercivity of approximately 1300 kA/m, and values of remanence and (BH)max were 0.62 T and 64 kJ/m3, respectively. It was also clarified that use of a Nd2.2Fe14B target together with the pulse annealing method is effective to increase remanence and (BH)max although the coercivity value decreased. ©2007 American Institute of Physics