Study on Fabrication Process of Anisotropic Injection Bonded Nd-Fe-B Magnets

摘要

This study is on the injection molding process for the fabricating anisotropic Nd-Fe-B bonded magnets. The effects of powder loading, particle size of the magnetic powder, polymer binder and the fabricating process on the magnetic and the mechanical properties of anisotropic Nd-Fe-B magnets were investigated. The proper powder loading, particle size and binder are 60%(vol%), 75-106 μm and PA1010, respectively. The optimum condition for good magnetic properties of anisotropic injection bonded Nd-Fe-B magnets is mixing the binder and the chemicals in the temperature between 205-215 ℃, injection temperature of 265 ℃, the injection pressure of 5-6 MPa, the press time of 5 second, and molding temperature of 80 ℃. The magnetic properties of anisotropic bonded Nd-Fe-B magnets made in above conditions from d-HDDR powder were: Br=0.72 T, iHc=983 kA/m, (BH)max=75 kJ/m3.