High Performance 1000℃ 3.2g/Cm³ Si3N4 Ceramic Bearings
Si3N4 Ceramic Bearings, Full Ceramic Bearings
Full ceramic bearing made with Si3N4 have some better performance than ZrO2, the rings and balls made by full ceramic material:Si3N4, as a standard contracture, the cage made by PTFE, generally we also could make the cage with GFRPA66-25,PEEK,PI, Phonemic Textiles Tube ,etc. Compares than the material of ZrO2, The SiN4 ceramics bearings could endure heavier load and could be used in higher temperature environment. Also we could offer precision ceramic bearing which generally used in high-speed and high-rigidity spindle. The manufactured clearance could be P4 to UP grade.
Comparison of bearing material technical data | ||||||
Technical data | unit | GCr15 | 9Cr18 | Si3N4 | AL203 | ZrO2 |
Density | g/cm³ | 7.8 | 7.9 | 3.2 | 3.95 | 6 |
a Coefficient of expansion | 10^-6/℃ | 11 | 17 | 3.2 | 9.1 | 10.5 |
E modulus of elasticity | Gpa | 208 | 200 | 320 | 380 | 210 |
μ Poisson ratio | 0.3 | 0.3 | 0.26 | 0.27 | 0.3 | |
HV Hardness | 800 | 700 | 1700 | 1800 | 1300 | |
δ Flexural strength | Mpa | 2400 | 2600 | 900 | 220 | 1000 |
δ Compressive Strength | MPa | 2000 | 1500 | 3500 | ||
Kc Impact strength | Nm/cm² | 20 | 25 | 7 | 3.5 | 11 |
λ Thermal conductivity | W/mk | 30-40 | 15 | 3.5 | 25 | 2.5 |
Ω Specific resistivity | mm²/m | 1 | 0.75 | 10^18 | 10^8 | 10^5 |
Specific heat | J/KgK | 450 | 450 | 800 | 880 | 400 |
Application temperature | ℃ | 120 | 150 | 1000 | 1850 | 800 |
Anti-corrossion | No | poor | Good | Good | Good | |
Cycle stress | 10*10^6 | 10*10^6 | 50*10^6 | 30*10^6 | 50*10^6 | |
Destroy model | peel | peel | peel | fracture | peel/fracture | |
Anti-magnetism | Yes | Yes | No | No | No | |
Dimension stability | bad | poor | Good | Good | Good | |
Insulate properties | No insulation | No insulation | Good | Good | Good |
Basic properties of staple engineer plastic | ||||||||
Material | HDPE | PP | POM | PA66 | PVDF | PPS | PTFE | PEEK |
Long-time working temp. | 90 | 100 | 110 | 100 | 150 | 230 | 260 | 280 |
Density | g/cm3 | 0.91 | 1.42 | 1.14 | 1.77 | 1.35 | 2.18 | 1.32 |
Ball indentation hardness | 50 | 80 | 170 | 170 | 80 | 190 | 30 | |
Tensile stress | 25 | 30 | 70 | 80 | 50 | 75 | 25 | 95 |
Sliding friction coefficient | 0.29 | 0.3 | 0.34 | 0.35-0.42 | 0.3 | 0.08-0.1 | 0.3-0.38 | |
Melted temperature | 130 | 165 | 175 | 260 | 172 | 280 | 327 | 343 |
Short-time highest application temperature | 90 | 140 | 150 | 170 | 150 | 260 | 260 | 300 |
Coet of Inear expansion (10^-5/K) | 13-15 | 17 | 10 | 8 | 13 | 5 | 12 | 5 |
Dielectric constant at 1 Mhz(10^6HZ) | 2.4 | 2.25 | 3.7 | 3.6-5 | 8 | 2.1 | 3.2-3.3 | |
Volume resisrivity (Ω·cm) | >10^15 | >10^24 | >10^14 | 10^13 | 10^12 | >10^13 | 10^14 | 10^13 |
flammability UL94 | + | + | - | (+) | (+) | - | + | + |
Anti-weathering | - | - | - | - | - | - | + | - |
Note: + =resistant; (+) =partly resistant; - =non-resistant |