Thermal Expansion of Glass Fabric-Epoxy Composites at Cryogenic Temperatures

Thermal expansion is a crucial parameter for the selection of material to be used along with any other materials in cryogenic system. This paper presents the analysis of such data obtained by a very precisely controlled experimental setup using 3‐terminal capacitance method. The measurements are carried out for the E‐glass fabric‐epoxy samples of 32.5%, 35.2%, 39.2% and 48.9% fibre concentration at perpendicular to the fabric direction. The results show that coefficient of thermal expansion (α) decreases with the increase of fibre concentration but increases with temperature. At 30K, α decreases about 32% when the fibre concentration increases from 32.5% to 48.9% and at 300K, it decreases to about 50%. Quantitative comparison of thermal expansion of composites is done with the stainless steel and epoxy. It is observed that at 32.5% and 48.9% of fibre concentration, thermal expansion decreases from 6% to 50% and 45.6% to 72.6% at 30K and 250K respectively. An attempt is made to prepare composite samples with different concentrations in order to make the thermal expansion very near to conventional metal. The best‐fit curves are developed on the basis of the experimental data, which will predict the thermal expansion values at any desired temperature and fibre concentration.