Question

what are the thermal properties of composite materials??? with references, please.

Answer 1

Thermal properties of Composite Materials are:

1. Thermal Conductivity: Thermal conductivity is the heat conduction nature of the composite. This depends on the material of the composite. If the composite materials are layered one above the other, then it can be found by series and parallel combinations. If it is a matrix then it can be found by using modelling methods. Normally it is the heat-conducting capacity of the material composite.
2. Thermal Diffusivity: Thermal diffusivity is the heat diffusing capacity of the material. This is proportional to the thermal conductivity ie., as conductivity increases, diffusivity also increases. Further, it increases with the increase in the fibre concentration.
3. Volumetric Heat Capacity: It is the capacity of the material to retain heat in it. Experiments show that the heat capacity of the composite will increase as the fibre content increases. This can be found out by using a calorimeter.
4. Thermal Expansion / Thermal Stress: This is a common phenomenon that occurs in each and every material upon heating or when exposed to heat. If it is composite laminate then the area of the mat increases, thus imparting stress in the fibres. If it is a matrix, then volumetric stress will be imparted due to the application of heat. This can be found out by using a constant known as the coefficient of thermal expansion.