BOND MAGNET AND FERRITE MAGNETIC POWDER FOR BOND MAGNET, INCLUDING ALKALI EARTH METAL AS COMPONENT AND ENSURING LESS DECREASE IN COERCIVITY WHEN MOLDED INTO BOND MAGNET

摘要

PURPOSE: A bond magnet and a ferrite magnetic powder are provided to prevent decrease in coercivity when molded into a bond magnet. CONSTITUTION: A ferrite magnet powder comprises an alkali earth metal as a component, and ensures decrease in coercivity of 6000e or lower when provided in a molding test. The molding test includes a step of mixing 90 weight parts magnetic powder, 0.4 weight parts silane coupling agent, 0.12 weight parts lubricant, and 9.48 weight parts nylon-6 powder; a step of producing a pellet having an average diameter of approximately 2mm by mixing the mixture at a temperature of 230 Deg.C.; a step of obtaining a cylindrical molded product having a diameter of 15mm and height of 8mm, by injection molding the pellet at a temperature of 290 Deg.C., molding pressure of 85 kgf/cm¬2, and a magnetic field orientation of 10 KgG; and a step of calculating a difference between the coercivity of the obtained molded product and coercivity of the magnetic powder, by measuring coercivity of the molded product through the use of a BH tracer.