Provided are a coated magnetic
abrasive particle and a preparation method thereof. The iron
ion based
molar ratio of iron dichloride to
ferric chloride of the coated magnetic
abrasive particle is 1 to 1-3, the
molar ratio of Fe ions to
ammonia water
ammonia ions is 1 to 2-7, the
mass ratio of ferroferric
oxide to a modifying agent is 1 to 5, an ethyl
alcohol-water solution is prepared according to the ethyl
alcohol-water proportion of 1 to 5, and the volume ratio of tetraethoxysilane to the solution is 1 to 20-30. Preparation is performed according to the volume ratio of
ammonia water to the solution. The preparation method comprises the preparation steps that 1, the iron dichloride, the
ferric chloride, the ammonia water, the modifying agent, ethyl
alcohol, the tetraethoxysilane and
distilled water are weighed; 2, the
distilled water and the
ferric chloride and the iron dichloride are mixed and prepared into a solution; 3, the ammonia water is added for stirring; 4,
drying is performed; 5, a
drying product, an activator and
distilled water are prepared into a solution, and dispersion is performed; 6, the alcohol-water solution is added for stirring; 7, the tetraethoxysilane is dropwise added; 8, the ammonia water is dropwise added and is stirred; 9,
drying is performed after product suction
filtration. The coated magnetic
abrasive particle is low in cost and easy to recover.