High Chromium Cast Grinding Ball, Extensively Used in Metal Mine, Coal Slurry, Thermal Power ... so that casting balls breakage is fewSurface hardness of ball will be raised further in using the course and ... reclaim ratio of extractive mineSpecifications: Ball diameter: 20 to 130mmMicrostructure: m+cHardness: 56HRCAbove specifications can be customized steel ball / High Chromium Cast Grinding Ball