Cearmic Bearing vs Steel Bearing Material Comparison

Ceramic Bearing vs. Steel Bearing Material Comparison Chart

Item

Unit

Si3N4

ZrO2

Al2O3 (99.5%)

SiC

Bearing Steel

Density

g/cm3

3.23

6.05

3.92

3.12

7.85

Water Absorption

%

0

0

0

0

0

Coeffficient of Linear Thermal Expansion

10-6/k

3.2

10.5

8.5

3

12.5

Modulus of Elasticity (Young's Mod.)

GPa

300

210

340

440

208

Poisson's Ratio

/

0.26

0.3

0.22

0.17

0.3

Hardness (Hv)

MPa

1500

1200

1650

2800

700

Flexural Strength (@ R.T.)

MPa

720

950

310

390

520 (tensile strength)

Flexural Strength (700°)

MPa

450

210

230

380

/

Compressive Strength (@R.T.)

MPa

2300

2000

1800

1800

/

Fracture Toughness, Kb

MPa*m1/2

6.2

10

4.2

3.9

25

Thermal Conductivity (@R.T.)

W/m*k

25

2

26

120

40

Electrical Resistivity (@R.T.)

Ω*mm2/m

>1013

>1015

>1016

>103

0.1~1

Max. Use Temperature (no loading)

°F

1050

750

1500

1700

300

Corrision Resistance

/

Excellent

Excellent

Excellent

Excellent

Poor