Composite abrasive particles for magnetic abrasive polishing and process for preparing the same

摘要

Composite abrasive particles for use in magnetic abrasive polishing in which three phases of corundum-phase alumina, alpha -iron and iron-alumina spinel are detected by the powder X-ray diffractometry and which contains 48 wt % or more of iron and 11 wt % or more of aluminum. The composite abrasive particles are prepared by mixing starting materials of powders of aluminum and an iron oxide in such a ratio that three phases of corundum-phase alumina, alpha -iron and iron-alumina spinel may coexist and so that iron may be contained in an amount of 48 wt % or more and aluminum may be contained in an amount of 11 wt % or more, subjecting the materials to a solid-phase exothermic reaction, and breaking the resultant solid product.