Composites at Cryogenic Temperature

Abstract

Fiber reinforced composites are class of materials that are workable engineering materials possessing high strength to weight ratio resulting in reduction of weight and hence savings in energy. Composites can be tailor -made to the required duty by changing the nature and proportion of the constituent materials. Composites exhibit anisotropy in mechanical and thermal properties. This makes the design of composite structures more complex and demanding. Composites have wide applications as supports and structures at cryogenic temperatures in super conducting magnets and as fuel tankage in spacecraft and rocketry. As these composites are fabricated at 1000 C to 2000 C, ~ their use at low temperatures creates thermal stresses. They become brittle at low temperatures and thermal strain of matrix ma:f be of the same order of the ultimate tensile strain at helium temperature (4.2K); thus leaving no more load bearing capability.