| 摘要 |
PURPOSE:To manufacture a rare earth permanent magnetic material having excellent mechanical characteristics by sintering the power molded body consisting of specific compsn. of rare earth elements, transition elements and B formed by adding specific amounts of specific rare earth elements-contg. alloy powder. CONSTITUTION:The alloy powder having the compsn. of 32-100wt.% R (R denotes rare earth elements including Y) is generated by a melt-quencing method. The alloy powder, 0-70vol.% (not including o), is added thereto to mold the powder having the compsn. consisting of, by atom., 15-40% R, 0.05-10% B and the balance consisting of T (T denotes transition elements). Said powder molded body is sintered to form a sintered body having substantially <=150mum potentially defective diameter. By this method, the title material contg. the double phase structure of R2T14B magnetic crystal grains and R-T solid solution can be obtd. As the testing method of its mechanical strength, the fracture toughness value is searched from the above magnetic crystal grains on the cracked surface generated in a fracture strength test. |
