To manufacture hermetic and highly insulating electrical seals between different materials such as metal or ceramics, the use of sealing glasses is wide spread in the electronics industry. Sealing glasses typically have a processing temperature of 800–1000°C.
Sealing glasses mostly belong to the borosilicate and aluminosilicate glass families.
To manufacture reliable hermetic seals, the correct choice of coefficient of thermal expansion (CTE) is a key factor. The applied glass composition depends on the materials which should be joined, the required temperature profile as well as their CTE. For matched seals, the CTE of the glass is matched as closely as possible to those of the sealing partners. In case of compression seals, a well-defined mismatch of the CTE is used intentionally to compress the sealing materials onto each other.
SCHOTT offers sealing glasses for both sealing concepts and a variety of materials ranging from silicon to stainless steel.
SCHOTT provides sealing glasses in the form of fine ground powder, paste, granulate and preforms.
SCHOTT provides Glass and Glass-Ceramic Sealants for Technical Ceramics in High-Temperature Applications. Please refer to the download tab for more information.
Glass powders are manufactured in two steps:
Features / Specifications
Please refer to the tables below to choose the right sealing glass for a variety of material combinations.
All sorts of sealing glasses are available in a number of different grain sizes.
Forms of Supply and Product Packaging
Our standard packaging consists of sealed PE-Bags in cardboard drums. For alternative packaging solutions please contact us.
Sealing glasses for high-temperature applications:
*CTE = coefficient of thermal expansion **p.c. = partially crystalline
For more information on the different quality assurance programs, please refer to our quality assurance processes.