Al2O3
|
Material
|
99%Al2O3
|
95%Al2O3
|
92%Al2O3
|
75%Al2O3
|
|||
|
Material Characteristics
|
Density
|
g/cm3
|
3.9
|
3.7
|
3.4-3.7
|
3.2-3.4
|
|
|
Water Absorption
|
%
|
< 0.5
|
< 1
|
< 2
|
< 2
|
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|
Sintering Temperature
|
°C
|
1,800
|
1,650
|
1,620
|
1520-1600
|
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|
Mechanical Characteristics
|
Vickers Hardness
|
Mo
|
12
|
10
|
12
|
10
|
|
|
Flexural Strength
|
kg/mm2
|
3,000-4,000
|
3,500
|
3,000
|
3,000
|
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|
Compressive Strength
|
kg/mm2
|
28,000-30,000
|
25,000-28,000
|
25,000
|
20,000
|
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|
Thermal Characteristics
|
Thermal Conductivity
|
25°C
W/m·k 300°C |
31.4
15.9 |
21.8 12.6 |
15-20
|
6-7
|
|
|
Max. Use Temperature
|
T(C)
|
1,600
|
1,000
|
1,600
|
1,350
|
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|
Coefficient of Linear Thermal Expansion
|
x10-6°C
|
6.4-8.2
|
5.5-7.5
|
7-7.6
|
7.3
|
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|
Melting Temp.
|
°C
|
1,750
|
1,600
|
1,500
|
1,300
|
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|
Electrical Characteristics
|
Dielectric Constant
|
(E)1MHz
|
9.2-11
|
9.4-9.8
|
9.2
|
8.3-9
|
|
|
Dielectric Loss Angle
|
tg
1MHz |
1-1.5
|
2-3.1
|
4
|
5-10
|
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|
Volume Resitivity
|
20°C
300°C 500°C |
Ω·cm
|
> 1014
>1013 >1012 |
> 1010
|
> 1010
|
> 1010
|
|
|
Dielectric Strength
|
KV/mm
|
25-30
|
17.6-20
|
35
|
25-30
|
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