Alumina grinding ball 
 Defined by bauxite, roller flour, industrial alumina powder, Alpha alumina powder high-temperature calcination of raw materials through ingredients, grinding, milling (pulp, mud system), forming, drying, firing, etc. process made, mainly as a grinding media ball is widely used stone. Depending on the alumina content, can be divided into the aluminum ball, high alumina ball and alumina ball in general we have 60% -65% alumina content of the plan for the aluminum ball, alumina content 75% -80% of known in the alumina ball, alumina content of 90% for the alumina ball. Which alumina ceramic ball is subdivided into 90, 92 ceramic, 95 ceramic and 99 porcelain. 99 porcelain because of its high production costs and there are few large manufacturers high-volume manufacturing, the key is part of the special ceramic factory by hand. 
 Chalco alumina ball and the ball due to its low price, and was accepted by the majority of ceramics factory, mainly used for grinding ceramic blank. Alumina ball due to its high strength, high hardness, high wear resistance, heavy, small size, high temperature, corrosion, pollution and other outstanding features have been widely used in different types of ceramic, enamel, glass, chemicals so thick factory finishing and deep processing of hard materials, particularly alumina content of 92 balls with the most common. 
 Laboratory testing of alumina grinding ball wear resistance and impact resistance of the method: 
 A1 principle of the method 
 This method is alumina ball in polyurethane tank to provide for the impact of ground conditions, assessment of the impact of performance goals, expressed in units of time to wear the wear resistance of alumina ball. 
 A2 grinding jar 
 Grinding can use polyurethane tank. Diameter 200mm, length 220mm 
 A3 wear impact testing machine 
 To ensure that the built-4kg of alumina ball mill and the A2 4L water tank to 80r/min continuous operation. 
 A4 test preparation 
 Appearance quality and appearance of the sample size of qualified about 4kg of alumina ball around, grinding into the A2 tank, plus 4L water, wear-resistant impact test machine in order to 80r/min grinding 2h. Remove the sample water to clean, dry spare. 
 A5 test procedure 
 A5.1 according to A4 sample after treatment, the amount of 0.1g with a sense of balance weighing m1; 
 A5.2 The samples were placed in A2 grinding jar, add the same weight of water, capping must not leaking into the wear test machine, so that the mill can grind to 80r/min after 24h downtime. 
 A5.3 grinding the sample from the tank removed, washing with water, dried and weighed m2. 
 A5.4 measured according to the provisions of the average diameter of 10 balls D. 
 A6 outcome 
 After impact, abrasion test no cracks, no broken, qualified as impact resistance. 
 EWT = KD (m1-m2) / m1 
 Where: EWT-wear ‰; 
 K-correction factor, 4.17X10-4 (mm) -1 
 D-ball, the average diameter, mm; 
 m1-sample from the total weight of the former mill, g; 
 m2-after grinding samples from the total weight, g