Ceramic balls possess stable comprehensive properties,especially for the silicon nitride balls.Compared with steel balls,they are lighter in weight and less in friction coefficient.The elasticity modulus of ceramics is 1.5 times higher than that of steels,while its thermal expansion coefficient is much lower.They are corrosion-resistant ,rust-resistant,antimagnetic,and could work under conditions of oil-free lubrication and high temperature(below 1000℃).
Due to the low density(3.20g/cm3 ),Si3N4 ceramic rolling bearings can effectively restrain the centrifugal force generated from high-speed rolling so as to bring down the load, which makes the ceramic ball bearings rotate sensitively and have good performances in oil-free lubrication conditions.Silicon nitride balls are specified for use in high-technology industry such as hybrid bearings,aerospace and defense.
| Rupture Strength | Minimum strength≥800Mpa（room temperature） |
| Chemical analysis | Aluminum 2.0~3.5 |
| Yttrium 4.0~5.0 | |
| Titanium 1.0~1.5 | |
| Oxygen 4.5~6.0 | |
| Microstructure | Porosity(>10μm) none |
| Volume Rating/ISO4505 0.02%max | |
| Inclusion. Ceramic 2nd phase(>25μm) none | |
| Metallic Phases(>10μm) none | |
| SEM Image | |
| Metallurgical Microscopes Image | |
| Frature Toughness | Kic=6.0~8.0 |
| Vicpers Hardness(HV20) | 1450~1600 Vicpers |
| Density | 3.24~3.27g/cm3 |
Grade | Size Range(Metric) | Size Range(Inch) |
| G10 | 1.5875~19.05 | 1/16~3/4 |
| G16 | 1.5875~19.05 | 1/16~3/4 |
| G20 | 1.5875~25.4 | 1/16~1 |
