Mechanical Properties Study of Hot-Pressed and Hot-Deformed Nd-Fe-B Magnets

The compressive strength, bending strength, and fracture toughness were investigated in hot-pressed and hot-deformed (HD) Nd-Fe-B magnets. The fracture behavior and its dependence on microstructure were analyzed. The results showed that magnets appear to be intergranular fracture. Additionally, the mechanical properties of HD magnets are isotropic, while that of HD magnets exhibit anisotropy owing to the shape anisotropy of grains. Moreover, the mechanical properties measured along the direction, which is parallel to pressing direction, are larger than that of perpendicular to pressing direction, and the gap of mechanical properties between two directions broadens obviously with the increase of hot deformation degree.

[1]  L. Ying,et al.  Effect of die-upset level on the mechanical properties and microstructure of Nd–Fe–B magnets prepared by spark plasma sintering , 2012 .

[2]  A. Yan,et al.  Effects of excessive grain growth on the magnetic and mechanical properties of hot-deformed NdFeB magnets , 2010 .

[3]  A. Yan,et al.  Enhanced magnetic properties and bending strength of hot deformed Nd-Fe-B magnets with Cu additions , 2010 .

[4]  Wuxia Li,et al.  Study on strengthening and toughening of sintered rare-earth permanent magnets , 2009 .

[5]  Wei Li,et al.  Sintered Nd-Fe-B magnets with improved impact stability , 2006 .

[6]  E. Shin,et al.  Enhancing Magnetic Properties of Bulk Anisotropic Nd–Fe–B/$alpha$-Fe Composite Magnets by Applying Powder Coating Technologies , 2006, IEEE Transactions on Magnetics.

[7]  H. M. Hosseini,et al.  The effects of MM38.2Co46.4Ni15.4 alloy additions on the mechanical properties of a Nd12.8Fe79.8B7.4-type sintered magnet , 2006 .

[8]  Wei Li,et al.  Anisotropic fracture behavior of sintered rare-earth permanent magnets , 2005, IEEE Transactions on Magnetics.

[9]  G. Warren,et al.  Comparison of the corrosion behavior of die-upset and sintered NdFeB magnets , 2001 .

[10]  Jian-sheng Wu,et al.  Influence of alloying elements on mechanical properties and microstructures of sintered Nd-Fe-Co-B magnet , 2000 .

[11]  D. Easton,et al.  Fracture Toughness of Nd2Fe14B Magnets , 1996 .

[12]  R. Mishra,et al.  The development of the microstructure of die-upset Nd-Fe-B magnets , 1990 .

[13]  R. Mishra,et al.  Grain growth and alignment in hot deformed Nd‐Fe‐B magnets , 1988 .