Mechanical Properties and Texture of Electrographitized Carbon

Abstract
The relations between mechanical properties and texture were discussed for six electrographitized carbons, whi ch had the known mixing ratios of coarse grain (3-0.5mm. in size), medium grain (less than 0.5mm.) and fine powder of a petroleum coke. Tensile strength was measured at various temperatures between room temperature and 2500°C. Young's modulus and bending strength were measured at room temperature. Themal expansion coefficient was calculated from the expansion between 20° and 100°C, apparent porosity from benzen immersion density and bulk density, and anisotropy factor from the orientation function of graphite crystallite.Electrographitized carbon was stronger under reduced pressure of 2×10-3 m mHg than in air by approximately 12%. Tensile strength measured various temperatures had a close relation to the grain size distribution. Both Young's modulus and thermal expansion coefficient could be also related to the grain size distribution using a similar formula. Tensile strength increased with increase in ambient temperature up to 2500°C. At 1100°, 1500°, 2000° and 2500°C, the ratios of high temperature strength to room temperature strength were approximately the same for all samples and the average values of the ratio were 1.19, 1.29, 1.50 and 1.76, respectively. The apparent linear relation between logarithm of strength and apparent porosity was found. The similar relation between logarithm of strength and anisotropy factor was also found.