Nd-Fe-B permanent magnets with a small amount of Cu nano-particles doping have been prepared by con-ventional sintered method. Effects of Cu content on magnetic properties, corrosion resistance, and oxidation properties of the magnets have been studied. It shows that the coercivity rises gradually, while the remanence decreases simultaneously with increasing Cu doping amount. Microstructure observation reveals that Cu ele- ment enriches mainly the Nd-rich phase. Autoclave test results show that the corrosion rate of the magnets decreases with increasing Cu content. After oxidation, the maximum energy product loss of the magnets with 0 and 0.2 wt% Cu nano-particles doping are 6.13% and 0.g9%, respectively. Therefore, it is concluded that Cu nano-particles doping is a promising way to enhance the coercivity and corrosion resistance of sintered Nd-Fe-B magnets.
Nd-Fe-B permanent magnets with a small amount of A1 nano-particles doping were prepared by conventional sintered method. Effect of AI content on magnetic property, corrosion resistance and oxidation properties of the magnets were studied. Inves- tigation showed that the coercivity rose gradually, while the remanence decreased simultaneously with increase of A1 doping amount. Further investigation revealed that most A1 element diffused into the main phase and some A1 element diffused into the Nd-rich phase The autoclave test results showed that the corrosion rate of the magnets decreased with A1 content increasing. After oxidation, the maximum energy product losses of the magnets with 0.0 wt.% and 0.2 wt.% AI nano-particles doping were 6.13% and 3.99%, respec- tively. Therefore, A1 nano-particles doping was a promising way to enhance the coercivity and corrosion resistance of sintered Nd-Fe-B magnet.
