Show me around

Aluminosilicate Glass SCHOTT 8252

Alternative and trade names
SCHOTT 8252
Want to keep this datasheet? Save it now in your required format

Description

Alkaline earth aluminosilicate glass for high temperature applications in electrical engineering, for sealing to molybdenum, free from alkali. Electrically highly insulating, high hydrolytic resistance, high resistance to thermal shock and high temperature resistance.

Ashby charts

See where Aluminosilicate Glass SCHOTT 8252 falls on the material property chart for Density against Elastic modulus in your materials selection and design process. Our Ashby charts are interactive with more technical data upon clicking. Sign up to get access to this premium feature for free.

Properties

General

Density

ρ

2.63 g/cm³ at 20 °C

Mechanical

Elastic modulus

E

81 GPa at 20 °C

Poisson's ratio

ν

0.24 [-] at 20 °C

Thermal

Annealing temperature

Tanneal

725 °C

Viscosity 10¹³ dPa.s (ISO 7884-4)

Coefficient of thermal expansion

α

4.6E-6 1/K at 20 °C

mean value for 20-300 °C - ISO 7991

Glass transition temperature

Tg

720 °C

ISO 7884-8

Softening temperature

Tsoftening

935 °C

Viscosity 10⁷·⁶ dPa.s (ISO 7884-3)

Specific electrical resistance temperature

Tk

660 °C

For ρ = 10⁸ Ω·cm

Strain temperature

Tstrain

670 °C

Viscosity 10¹⁴·⁵ dPa.s (ISO 7884-7)

Thermal conductivity

λ

1.1 W/(m·K) at 90 °C

Working temperature

Tworking

1240 °C

Viscosity 10⁴ dPa.s (ISO 7884-2)

Electrical

Dielectric constant, 1MHz

εr,1MHz

6.1 [-] at 20 °C

Electrical resistivity

ρel

1.00E+10 Ω·m at 350 °C

Loss tangent, 1MHz

tanδ1,MHz

1.1E-3 [-] at 20 °C

Optical

Refractive index

nd

1.54 [-]

at λ=587.6 nm

Stress optical coefficient

k

2.8E-6 mm²/N

DIN 52314

UV transmission

tUV

58 %

max., Thickness=1 mm, λ=330 nm

Chemical properties

Element

Weight %

Comment

Other

0.01 %

max., Lead, Cadmium, Mercury and Hexavalent Chromium

Technological properties

Application areas

For high temperature applications in electrical engineering. For use in bulb and exhaust tube, for halogen lamps for automotive, houshold, general lighting and Exterior lighting

Corrosion properties

Hydrolytic resistance Class HGB1 (ISO 719) - Acid resistance Class S3 (DIN 12116) - Alkali resistance Class A2 (ISO695)

Do you need more data regarding this material?

This material data has been provided by Schott Glass Tubing.

All metrics apply to room temperature unless otherwise stated. SI units used unless otherwise stated.
Equivalent standards are similar to one or more standards provided by the supplier. Some equivalent standards may be stricter whereas others may be outside the bounds of the original standard.