White alumina ceramics

 magnesia porcelain

 black alumina ceramics

Al2O3 Contents

80

90

95

99

92

Firing temperature ()

1650

1700

1720

1800

1350

1700

Volume concentrationg/cm3)

3.3

3.6

3.7

3.85

2.9

3.8

Resistance to bendingMPa)

220

320

280

490

180

210

linear expansibility ×10-6/25°800

7.6

7.2

7.6

7.6

7.5

7.5

×10-6/25°800

coefficient of heat conductivity w/m.k) 

17

17

21

37

17

insulating coefficientkv/mm)

10

12

12

12

15

10

insulating coefficientkv/mm)

20

>1014

>1014

>1014

>1014

>1014

>1012

300

>1013

>1013

>1012

>1010

>1013

>108

Kε1MHz) 

8

8.5

9.4

10.5

6

7.9

tgδ×10-4(1MHz)

13

3

2

<1

8

εtgδ×10-4

104

26

19

<10