R-T-B-BASED ALLOY POWDER, AND COMPOUND FOR ANISOTROPIC BOND MAGNET AND ANISOTROPIC BOND MAGNET

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PROBLEM TO BE SOLVED : To provide an R-T-B-based alloy powder having a sufficiently high coercive force. SOLUTION : An R-T-B-based alloy powder (where, R is one kind or more of rare earth element, T is an element consisting of at least one kind of iron and cobalt), is composed of main phase particles 24 consisting of R2T14B and having an average grain size of 200-500 nm, a grain boundary phase 25 of more R-rich composition than the main phase particles, and an additive phase. On an arbitrary cross section of the R-T-B-based alloy powder, the ratio of the sum of the peripheral length of the grain boundary phase and the sum of the peripheral lengths of the main phase particles is defined by a formula 1 as a coverage factor. The coverage factor of the main phase particles by the grain boundary phase having a circularity of 0.1-0.6 defined by a specific formula is 10-40%. COPYRIGHT : (C)2013, JPO&INPIT