Prediction of interfacial thermal resistance of carbon fiber in one dimensional fiber-reinforced composites using laser flash analysis

Laser flash analysis (LFA) is a sophisticated method to access the thermal diffusivity of homogeneous planar samples with very little effort. LFA measurement on fiber-reinforced composites, however, often generates inconsistent results due to violation of homogeneous assumptions. We propose a computational method to reduce this inconsistency. The method compares the radiometer signals of one dimensional carbon fiber-reinforced composite from LFA measurement and the finite element simulation results to predict the interfacial thermal resistance and the axial thermal conductivity of carbon fiber. The thermal conductivities of the composite under different environmental temperature are obtained. Agreement between the simulation signal curves and the experiment signal curves is within 5% error during the main temperature rise. The method extends the functionality of LFA to measuring thermal conductivity of complex composite with known microscopic structure, and provides a way to estimate microscopic parameters and to evaluate macroscopic and microscopic effect of different preparation methods.