Patent ID: 8500921

Claim:
A manufacturing method of a Nd—Fe—B based permanent magnet comprising steps of milling magnet material into magnet powder; adding an organometallic compound expressed with a structural formula of M-(OR) x , M representing V, Mo, Zr, Ta, Ti, W or Nb, R representing a substituent group consisting of a straight-chain or branched-chain hydrocarbon, and x representing an arbitrary integer, to the magnet powder obtained at the step of milling magnet material and getting the organometallic compound adhered to particle surfaces of the magnet powder; calcining the magnet powder of which particle surfaces have got adhesion of the organometallic compound in hydrogen atmosphere so as to obtain a calcined body; compacting the calcined body so as to obtain a compact body; and sintering the compact body, wherein the permanent magnet is Nd—Fe—B based.