Item | The national standard steel grit | High quality steel grit | |
Chemical Composition % | C | 0.85-1.20 | 0.85-1.0 |
Si | 0.40-1.20 | 0.70-1.0 | |
Mn | 0.60-1.20 | 0.75-1.0 | |
S | <0.05 | <0.030 | |
P | <0.05 | <0.030 | |
Hardness | GP | HRC46-50 | HRC46-50 |
GL | HRC56-60 | HRC56-60 | |
GH | HRC63-65 | HRC63-65 | |
Density | ≥7.40 g/cm3 | 7.6 g/cm3 | |
Microstructure | Tempered martensite | Tempered martensite and bainite | |
External form | Polygon Spherical, hemispherical, flat Grain<10% | Polygon Spherical, hemispherical, flat Grain<5% |