Product Name: Grinding Media Balls (dia20-130mm) Model NO.: 20-130mm Size: Dia20-150mm Processing Type: Casting Usage: Cement, Mine Material: Steel Chrome Content: 2-12% HRC: 55-62 Microstructure: M+C MOQ: 10 Metric Tons Trademark: Xinning Transport Package: Strong Nylon Bags, Steel Drums Origin: Anhui, China Product Description Casting alloyed grinding ball, mill balls, grinding chrome steel ball.With high hardness and wear-resistance, .The chrome can be adjusted as customers' requirement, <o: P>The size can be 12.7mm-150mm, <o: P>Hardness from 45~62, <o: P>If need special grade hardness or other, we also can adjust and match your need.Chemical Composition (%)NameCSiMnCrSPhigh-chrome balls1.8-3.20.3-1.2≤2.010.0-12.0≤0.1≤0.1Mid-chrome balls1.8-3.20.3-1.20.3-1.03.0-5.5≤0.13≤0.11low-chrome balls2.2-3.5≤1.2≤1.0≤2.0≤0.1≤0.1NameHardnessImpact Value AK (j/cm2)Micro structureEndurance Test Times(5m)high-chrome balls55-62≥2.5M+C≤Φ80≥15000≥Φ80≥10000Mid-chrome balls≥47≥2.0P+C≤Φ80≥13000≥Φ80≥6000low-chrome balls≥45≥1.6P+C≤Φ80≥Φ80≥5000