Measurement of Radial Thermal Expansivity of Carbon Fiber

Abstract

Image analysis method was used to measure the radial thermal expansion coefficient of carbon fiber. Diameter of the carbon fiber was determined at each temperature up to 1000°C, by the analysis of SEM image introduced into a image analyzer. The thermal expansion coefficient was also obtained from calculation of the Bacon's equation, in which the orientation function measured by X-ray method was used with the thermal expansion coefficients of single crystal reported in literature. There was an acceptable agreement between the thermal expansion coefficients obtained by the two different ways. It was shown that the analysis of SEM image was an useful method to measure the radial thermal expansion coefficient of carbon fiber.