GB/T 5611 established and the following terms and attributes shall apply to this standard

3.1 Chrome alloyed cast iron grinding ball

The white cast iron with chromium as main alloy element is called chrome alloy cast iron for short, and the cast grinding ball with chrome alloy cast iron as material is called chrome alloy cast iron grinding ball

3.2 Ductile cast iron grinding ball

The casting grinding balls made of nodular cast iron are called nodular cast iron grinding balls, in which the Bainite nodular cast iron grinding balls are obtained by heat treatment；The matrix structure obtained by heat treatment is mainly the spheroidal graphite cast iron grinding ball which is called martensite ductile iron grinding ball.

3.2 Breakage ratio of the grinding media

Broken ball is refers to broken area more than 1 / 3 of the ball area, the use of the process of broken ball total mass and the total use of balls mass percentage known as the broken rate.

3.4 Impact fatigues life of balls

The impact fatigue life of the grinding ball is defined as the number of times that the grinding ball is subjected to impact fatigue during the ball dropping test