Hybridization of carbon–glass epoxy composites: An approach to achieve low coefficient of thermal expansion at cryogenic temperatures

The paper is based on a study to develop carbon–glass epoxy hybrid composites with desirable thermal properties for applications at cryogenic temperatures. It analyzes the coefficient of thermal expansion of carbon–epoxy and glass–epoxy composite materials and compares it with the properties of carbon–glass epoxy hybrid composites in the temperature range 300 K to 125 K. Urethane modified epoxy matrix system is used to make the composite specimens suitable for use even for temperatures as low as 20 K. It is noted that the lay-up with 80% of carbon fibers in the total volume fraction of fibers oriented at 30° and 20% of glass fibers oriented at 0° yields near to zero coefficient of thermal expansion as the temperature is lowered from ambient to 125 K.

Research highlights
► Achieved near zero expansion at 125K with carbon-glass hybrid composites.
► Urethane modified matrix system gave promising mechanical properties at 20K.
► Effective usage of negative expansion of carbon and positive expansion of glass.