| Items | Units | Bearing Steel | Stainless Steel | Ceramic Si3N4 | Ceramic ZrO2 | Ceramic Al 2O3 |
| Density | g/cm3 | 7.85 | 7.90 | 3.20~3.30 | 6.00 | 3.95 |
| Coefficient of linear expansion | 10-6/ K | 10.0 | 11.0 | 3.2 | 10.5 | 8.5 |
| Young’s Modulus | GPa | 208 | 200 | 300~320 | 210 | 380 |
| Poisson’s ratio | -- | 0.30 | 0.30 | 0.26 | 0.30 | 0.22 |
| Hardness | Hv10HRc | 700 62 | 66 | 1500~1800 75~80 | 1200 70 | 1800 80 |
| Bending strength | MPa | 2400 | -- | 800~1000 | 950~1200 | 300~500 |
| Fracture toughness | MPam-1/2 | 25 | -- | 6.0~7.0 | 10.0 | 3~4 |
| Thermal conductivity | W/mk | 30~40 | 15 | 35 | 2~3 | 30 |
| Special electrical resistance | Omm2/m | 0.1~1 | 0.75 | 1018 | 1015 | 1018 |
| Heat resistance | C | 120 | 300 | 800 | -- | -- |
| Corrosion resistance | -- | Low | Medium | High | High | High |
| Stress cycles(50% failed) | -- | 10×107 | -- | 10×107 | 10×105 | |
| Nonlubrication friction | -- | High | High | Low | -- | -- |
| Magnetism | -- | magnetic | magnetic | non- magnetic | non- magnetic | non- magnetic |
| Centrifugal force | -- | Very high | Very high | Very low | High | medium |
| Operate temperature increasing | -- | high | high | low | -- | -- |
| Size stability | -- | Low | Low | High | High | High |
| Conductivity | -- | conductor | conductor | insulator | insulator | insulator |
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