Effect of Dy₇₀Cu₁₅Ga₁₅ Grain Boundary Diffusion on the Microstructure and Properties of Sintered Nd-Fe-B Magnets AITranslate

Basic Information:

DOI：

Chinese Library Classification Number:TM273[一般工业技术]

Citation Information:

Reducing the use of expensive heavy rare earth elements(such as Dy and Tb)is the key to pro-ducing low-cost,high-performance sintered Nd-Fe-B materials.In this paper,low heavy rare earth alloy Dy₇₀Cu₁₅Ga₁₅ was used as the diffusion source to treat sintered Nd-Fe-B magnet by grain boundary diffu-sion(GBD)technology.The effects of GBD on the properties and microstructure of the magnets were ana-lyzed,and the service performance was characterized.The results show that the coercivity of the sintered Nd-Fe-B magnets significantly increases by 57%after GBD treatment,and the remanence and maximum magnetic energy product slightly decrease.The diffusion of alloying elements into the grain boundary phase optimizes the microstructure of the magnets,and forms a(Nd,Dy)₂Fe₁₄B hard magnetic phase shell on the surface of the matrix grain,mitigating the boundary defects and enhancing the magnetocrystalline anisotro-py field.The magnetic flux loss of the GBD magnet after high temperature treatment is reduced,indicating an improvement in its high temperature stability.Compared with the original magnets,the GBD magnet exhibits better corrosion resistance,with an increase of 18.7% in corrosion potential and a reduction in cor-rosion current density by 54.7% under electrochemical corrosion conditions.