Abrasive Alumina ball: 1.size:20mm,25mm,30mm,40mm,50mm,60mm,70mm 2.alumina content:95 ... Features:1. High wear-resisting: The alumina balls’ wear resisting is higher than ... When it is working, the ball will not pollute the grinded materials, ... improve the grinding efficiency. Index for alumina grinding balls: Product Al2O3(%)Density(g ... The standard specification of alumina grinding balls Diameter(mm)φ25φ ...