(RARE EARTH)-IRON-BORON MAGNETIC ALLOY AND ITS PRODUCTION AND BOND MAGNET USING THE (RARE EARTH)-IRON-BORON MAGNETIC ALLOY

摘要

PROBLEM TO BE SOLVED: To obtain high residual magnetic flux density and high coercive force by specifying the composition of elements and the constitution of alloy structure, respectively. ;SOLUTION: This alloy has a composition represented by the formula, R_xFe_100-x-y-z-wCO_yM_zB_w [where R is one or more kinds among five rare earth elements such as Nd, M is one or more kinds among 14 elements such as Ti, and 5≤x≤10, 0≤y≤9.0, 0.1≤z≤5, 2≤w≤7, 9≤(x+w), and 5(y+z) are satisfied]. Moreover, this alloy has an alloy structure in which soft magnetic crystalline phases, containing solid solution of αFe, bccFe, and the above M, and hard magnetic crystalline phases, composed of Nb₂Fe₁₄B₁ type tetragonal system crystal, are precipitated in soft magnetic amorphous phases, respectively. Further, by regulating the area ratios of these amorphous phases and crystalline phases to respectively prescribed values, residual magnetic flux density as high as ≥10kG and coercive force as high as ≥3.5kOe can be obtained, and, as a result the alloy, having high maximum energy product and excellent in rust- preventing property, can be obtained.;COPYRIGHT: (C)1998,JPO