| 摘要 |
<p>PURPOSE:To carry out the speedy mirror surface finishing having the excellent surface smoothness, exceedingly suppressing the generation of scratch, etc., in the polishing finishing by forming a soft material for a soft member from the alpha-alumina particle having a relative polishing speed for the ferrite single crystal of a prescribed value or more. CONSTITUTION:A polishing material for a soft member consists of alpha-alumina particles having a relative polishing speed for the ferrite single crystal of 300% or less and an average primary particle diameter of 0.1-1.0mum. Accordingly, in comparison with the case where the polishing time of 90min. is necessary with a solid portion concentration of 6wt.% in use of magnesia, the solid portion concentration can be reduced to about 2wt.%, and also the polishing time can be reduced to about 20min. by using alpha-alumina. Further, the fine polishing work for the soft member can be carried out with the excellent surface smoothness in an aqueous solution.</p> |
