Si3N4 ceramic is one kind atomic crystal industrial ceramic. It has the
characteristics of wear resistance, high temperature resistance,
high temprerature strength, high thermal stability, resistance to
most metal solutions and acid-alkali corrosion, high thermal
conductivity and good insulation performance. It is a new material
with the best comprehensive performance.
Features
• Excellent compactness and high strength
• Excellent thermal conductivity and thermal-shock resistance
• High hardness, self lubrication and good wear resistance
• Low thermal expansion coefficient and high temperature resistance
• No infiltration with aluminum and other non-ferrous molten
metals, good corrosion resistance
Ceramic bearings have developed rapidly since 1972. It has been
widely used in precision machine tools, automobiles, aeroengines,
chemical instruments, superconducting devices and other fields. As
a bearing material, the most basic characteristic is the rolling
fatigue life. In order to evaluate the applicability of various
ceramic bearings, the rolling life test of ceramic plate is carried
out, and the order of rolling life is alumina < silicon carbide
< zirconia < silicon nitride. It can be seen that Si3N4 is the most suitable bearing material among the above four common
engineering structural ceramics.
Technical Specification:
Silicon Nitride Balls are very high-cost grinding media that are
used for milling same materials (silicon nitride ball to mill
silicon nitride materials) to avoid contamination. They are now
available in 2mm and 3mm and sizes up to 25mm. They are a special
order item.
Silicon Nitride Ceramic Ball Accuracy Grade(μm)
(GB/T 308.2-2010(E) Standard)
| Grade | Vdws | ΔSPH | Vdwl | Ra |
| G3 | ≤0.08 | ≤0.08 | ＜0.13 | ≤0.01 |
| G5 | ≤0.13 | ≤0.13 | ＜0.25 | ≤0.014 |
| G10 | ≤0.25 | ≤0.25 | ＜0.5 | ≤0.02 |
| G16 | ≤0.4 | ≤0.4 | ＜0.8 | ≤0.025 |
| G20 | ≤0.5 | ≤0.5 | ＜1 | ≤0.032 |
Advantages of Silicon Nitride Bearing balls:
| Properties | Ordinary Steel Ball | Silicon Nitride Balls | Evaluations |
| Density(kg/cm3) | 7800 | ≥3220 | The lower the density, the less energy loss |
| Young's Modulus (GPa) | 210 | ≥300 | The higher the modulus number, the smaller the deformation |
| Vickers-hardness(GPa) | 8 | 14-18 | The higher the hardness, the better the rigidity |
| Toughness (MPa·m) | 16-25 | 6-8 | The higher the toughness, the better the impact resistance |
| Thermal Expansion Rate(10-6/K) | 12 | ≤3 | The lower the thermal expansion rate, the smaller the deformation |
| Specific Heat Capacity(J/kg·K) | 450 | 650 | The larger the specific heat, the smaller the temperature change |
| Use Upper Limit Temperature(℃) | 230 | 1000 | The higher the online temperature, the wider the application field |
| Minimum Surface Roughness(μm) | 0.02 | 0.004-0.005 | The smaller the surface roughness, the smoother |
| Compressive Strength (MPa) | 7.5 | ≥3000 | The higher the compressive strength, the longer the life |
| Resistivity (Ω·cm) | 0.001 | 10^14 | The higher the resistivity, the better the insulation |
