Abstract
The main problems with the sintered NdFeB magnets are their bad formability, low oxidation resistance, and poor temperature stability. Relatively large grain size, typically more than 3 mm, is also not beneficial to the high coercivity. Current efforts are directed to improve the magnetic properties and reduce the cost of NdFeB magnets by compositional modification, microstructure optimization, and new process employment. Spark plasma sintering (SPS) is one of the novel sintering techniques for preparing NdFeB magnets in a laboratory scale. Low sintering temperature and short holding time make it possible to sinter nanocrystalline NdFeB powders into fully dense bulk magnet. However, it is still not possible to completely avoid the grain coarsening, which leads to inevitable decrease of coercivity. To improve coercivity, the magnetic powders can be mixed with some metal powders such as Cu and Zn, which are beneficial for densification during SPS. Another effective way to enhance the coercivity is to add the powdered Dy compounds. In this paper, we report the effects of separated and combined Dy 2 O 3 and Zn additions on the magnetic properties, microstructure and thermal stability of SPSed nanocrystalline NdFeB magnets.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.