Effects of the Disproportionation Stage of the HDDR Process on Magnetic Properties and Microstructure of Pr $_13$Fe $_80$B $_7$ Alloys

• Published in: IEEE transactions on magnetics 2006-12, Vol.42 (12), p.3880-3882
• Main Authors: Han, J., Liu, S., Wang, C., Du, H., Chen, H., Dong, S., Yang, Y.
• Format: Article
• Language: English
• Subjects: Alloys; Coercive force; Disproportionation; Heat treatment; Hydrogen storage; Magnetic properties; Magnetism; Microstructure; Vanadium
• ISSN: 0018-9464; 1941-0069
• DOI: 10.1109/TMAG.2006.885434

Effects of the heat treatment conditions of the disproportionation stage on magnetic properties of hydrogenation disproportionation desorption recombination (HDDR) Pr sub(13)Fe sub(80)B sub(7 ) material are investigated. The results show that the HDDR Pr sub(13)Fe sub(80)B sub(7 ) material disproportionated by heating from room temperature under hydrogen (C-HD), has high coercivities and low remanences while that heated up to 800degC under vacuum, and then disproprotionated by exposing to hydrogen (V-HD), show high remanences with low coercivities. Further investigations show that this difference of magnetic properties of HDDR Pr sub(13)Fe sub(80 )B sub(7) materials, which is caused by the C-HD and V-HD treatment, might be related to the disproportionation at low temperature (650degC) in the C-HD treatment. At the same time, it is also found that the microstructure of the Pr sub(13)Fe sub(80)B sub(7 ) alloys disproportionated by C-HD treatment is mainly spherical while that of the alloys disproportionated by V-HD treatment is mainly rod-like