Item

Unit

Performance

Alumina ceramic

steatite ceramic

90%

92%

95%

96%

Ceramic

Body

Appearance

Colour

-

white,ivory white,brown,black

white,off-white

Mechanical

Characters

Bulk Density

g/cm3

≥3.6

≥3.65

≥3.7

≥3..75

2.7

Water Absorption

%

0

0

Flexural strength

MPa

280

300

310

320

150

(HV)

Hardness

GPa

12

5.8

Thermal

Characters

Coefficient of linear thermal expansion

20℃~800℃

×10-6mm/℃

6.3~7.3

6.4~7.4

6.5~7.5

6.8~7.8

8.0

Thermal Conductivity

W/(m.K)

12

16

20

23

2

Electrical

Characters

(1MHz)

Dielectric constant(1MHz)

—

9~10

9~10

9~10

10

7.5

Dielectric loss angle

×10-4

≤6

≤5

≤4

≤3

8

Dielectric Strength

KV/mm

15

20

24

28

18

Metalized Ceramics

Gas leakage coefficient

Pa.m3/s

≤10-8

-

Volume resistivity

Ω.cm

≥1015

-

Combined strength

MPa

≥120

-

Thickness of Metal

μm

≥20

-