Abstract
This paper presents measurement technique of the distribution of anisotropy and the in-plane thermal diffusivity for the pitch-based carbon fiber reinforced plastics (CFRPs). The measurement was conducted by using a laser-spot periodic heating method. The temperature of the sample is detected by using a lock-in thermography. The thermography can analyze the phase difference between periodic heat input and temperature response of the sample. Two kinds of samples, unidirectional (UD) and cross-ply (CP) CFRPs, were fabricated. All carbon fibers of the UD sample run in one direction [0°]. The carbon fibers of the CP sample run in two directions [0°/90°]. It is found that, by using the lock-in thermography, it is able to visualize the degree of thermal anisotropy and calculate the angular dependence of the in-plane thermal diffusivity of the CFRP. Thermal conductivities of these samples were also calculated from the measured thermal diffusivity, specific heat, and density.
