A feasibility study of fiber orientation determination in carbon-carbon composites using laser point source heating

The purpose of this thesis is to discuss the point heat source method as a way to determine the fiber orientation in different Carbon-Carbon (C/C) composite samples. A high power, double-pumped, Nd-Yag laser was used to heat a small circular area, approximately a 1 mm in diameter, on the C/C sample. An infrared thermographic camera recorded the change in temperature on the surface. An isotherm in the shape of a scalene ellipse formed from the different coefficients of heat conduction in the three principle directions. Models were constructed using Finite Element Analysis (FEA) to predict the effects of changes in fiber orientation through thickness on the surface isotherm. Additionally, a new method to potentially detect defects in C/C was discovered.