1. CAS Key Laboratory of Magnetic Materials and Devices, Zhejiang Province Key Laboratory of Magnetic Materials and Application Technology, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo 315201, China
2. School of Materials Science and Engineering, Shanghai University, Shanghai 200072, China
3. Baotou Hidyree Technology Co., Ltd., Baotou 014030, China
4. Hangzhou Permanent Magnet Group Co., Ltd., Hangzhou 311231, China