GCr15 AISI440C Hybrid Ceramic Ball Bearings For Inner / Outer Ring
Hybrid construction ceramic ball bearings
Ceramic ball especially Si3N4 have the following performance as low density, high strength, low friction coefficient, electrical and magnetism resistance, wear resistance, well rigidity, lubrication and maintenance free when working, the best choice for rollers (inner ring and outer ring are made by metal) of the hybrid construction ceramic ball bearing which are used in high-speed, high accuracy and long life environments. Normally, GCr15, AISI440C, 316, 304 makes inner ring and outer ring. The ceramic ball can adopt ZrO2, Si3N4 or Sic material.
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 |