Steatite

Property

ASTM
Method

Units

L-4

L-5

Color

-

-

tan

gray-green

Gas Permeability

-

-

n/a

n/a

Density

C 20-97

g/cc

2.65

2.75

Hardness

-

Mohs Scale

7

7

Water Absorption

C 20-97

%

0

0

Flexural Strength

F417-87

psi

17,000

20,000

Tensile Strength

-

psi

10,000

10,000

Compressive Strength

-

psi

80,000

85,000

Elastic Modulus

C848

psi x10⁶

15

15

Shear Modulus

C848

psi x10⁶

6

6

Poisson's Ratio

C848

none

0.24

0.24

C.T.E., 25 - 100°C

C372-96

x10^-6/°C

7.3

8.5

C.T.E., 25 - 300°C

-

-

7.4

8.6

C.T.E., 25 - 600°C

-

-

7.5

8.6

Thermal Conductivity,
25°C

C408

W/m-K

3

3

Max Use Temperature
(Non-Loading)

-

°F

2350

2350

-

°C

1290

1290

Dielectric Strength
(.125" Thick)

D149-97A

V/mil

260

270

Dielectric Constant @ 1MHz

D150-98

-

5.6

5.7

Dielectric Constant

D2520-95

-

5.6

5.8

@GHz

@9.2

@12.5

Dielectric Loss @ 1MHz

D150-98

-

0.003

0.0014

Dielectric Loss

D2520-95

-

0.005

0.0017

@GHz

@9.2

@12.5

Volume Resistivity,
@25°C

D257

ohms-cm

>1E +14

>1E +14

Volume Resistivity,
@300°C

-

-

2E +13

1E +11

Volume Resistivity,
@700°C

-

-

2E +09

2E +10

Note: The information in this data sheet is for design guidance only. STC does not warrant this data as absolute values. Forming methods and specific geometry could affect properties. Slight adjustments can be made to some of the properties to accommodate specific customer requirements. Most of the dense materials in the table are resistant to mechanical erosion and chemical attack. STC has performed ASTM testing qualification for certain compositions, in accordance with ASTM D2442. Please consult our technical staff for appropriate material and specifc test results.

Note: In addition to the above compositions, STC offers a wide range of alternative materials. Please contact one of our applications engineers for material requirements that may not be shown above.