DIA 20-150mm ; ( HRC45-65 ) 1) High Hardness: Huamin forged grinding steel ball has high hardness: surface hardness can reach to 55-67 HRC, volume hardness 56-64 HRC 2) High Impact Toughness: impact toughness is more than 12 J / cm2. 3) Low Broken Rate: peel fragmentation resistance property of over 20000 times. The actual breakage rate is less than 1% and close to 0.
