4D carbon-carbon composite processing and its properties in comparison with other carbon-carbon preforms

The re-entry structure of a long range missile will experience severe aero thermal load during flight. The nose tip of the missile shall be capable of withstanding these severe thermal stresses arising out of thermal shock in all the directions. The material has to be so designed as to exhibit symmetric erosion and should have the lowest erosion rate with respect to all directions. So multidirectional reinforced carbon-carbon composite is an ideal choice for this application. To obtain strength in 2, 3 or 4 directions we weave fibers in different directions. Though carbon-carbon composite shows anisotropic (direction dependent) property, 4D carbon-carbon composite shows the same properties (strength, erosion rate, etc) in all 4 directions. The process involved for making 4D carbon-carbon is very tedious as well as very expensive. The properties like density, tensile strength, specific modulus, etc are studied and are very much comparable with those of the other preforms.