POWDER FOR R-FE-B ANISOTROPIC MAGNET AND MANUFACTURE OF BONDED MAGNET USING SAME

摘要

PURPOSE:To prevent the distortion and destruction of the title magnet at the time of molding so as to improve the orientational property and magnetic property of the magnet by forming particles of R-Fe-B alloy powder (R: a rare earth element containing Y) to granulated particles composed of small pieces which are thinner in their c-axis and piled up in the c-axis direction, with the length in the c-axis direction being made equal to or shorter than the length in another crystal-axis direction. CONSTITUTION:Anisotropic powder prepared by pulverizing thin bands obtained by quenching an R-Fe-B (R: a rare earth element containing Y) liquid after hot upsetting is preformed at a low pressure (0-3 tons/cm<2>) in a magnetically oriented state and the preformed body is tentatively sintered at 600-900 deg.C. Then granulated particles are obtained by pulverizing the tentatively sintered body in such a state where the sintered body is put between tow metallic plates 6 and 7 of stainless steel in a stainless steel container 8 and a mobile yoke 1 is moved upward and downward as a hammer under a magnetic field applied condition. The granulated particles thus prepared are composed of small pieces which are thinner in their c-axis direction and piled up in the c-axis direction, with the length in the c-axis direction being equal to or shorter than the length in another crystal axis direction. Such granulated particles are used for making this R-Fe-B anisotropic magnet.