ALBERT

Description: 〈p〉Publication date: 1 October 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Acta Materialia, Volume 178〈/p〉 〈p〉Author(s): Satoshi Okamoto, Kazunori Miyazawa, Takahiro Yomogita, Nobuaki Kikuchi, Osamu Kitakami, Kentaro Toyoki, David Billington, Yoshinori Kotani, Tetsuya Nakamura, Taisuke Sasaki, Tadakatsu Ohkubo, Kazuhiro Hono, Yukio Takada, Takashi Sato, Yuji Kaneko, Akira Kato〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉A Ga-doped Nd-Fe-B sintered magnet has attracted significant attention as a heavy-rare-earth-free high-performance magnet. We have studied the temperature dependent magnetization reversal process of a Ga-doped Nd-Fe-B sintered magnet based on the first-order reversal curve (FORC) analysis. The FORC diagram pattern of the Ga-doped Nd-Fe-B sintered magnet changes from single spot in the high field region at room temperature to double spots in the low and high field regions at 200 °C, indicating that the dominant magnetization reversal process changes from single domain type to multidomain type. The single domain magnetization reversal at room temperature is well confirmed by using the soft X-ray magnetic circular dichroism microscopy observation. This change in the magnetization reversal process is well discussed by the temperature dependent local demagnetization field and the saturation field of multidomain state. Moreover, we have demonstrated the quantitative analysis of the FORC diagram pattern, which makes a deeper understanding of the magnetization reversal process of the Ga-doped Nd-Fe-B sintered magnet.〈/p〉〈/div〉 〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S1359645419305063-fx1.jpg" width="500" alt="Image 1" title="Image 1"〉〈/figure〉〈/p〉〈/div〉