Mechanical Properties of Structural Carbon-Carbon Layered Material at High Temperatures

Resumo

The results of tensile and compression tests performed for a layered carbon-carbon material in the range of 20–3000°C are presented. The material has been developed using chopped high-modulus VPR-19C fiber and coke obtained by repeatable thermomechanical treatment of bakelite lacquer LBS-1 and subsequent pyropacking resulting from carbon saturation from the gas phase at 1000°C. The production technology provides a transverse anisotropy of the material structure and, accordingly, the mechanical properties. In the course of compression tests in the direction parallel to the pressing axis at room temperature, it has been found that, when the sample height increases by a factor of 6, the material elastic modulus increases by a factor of 1.4, which is accompanied by a 2.4-fold decrease in the compression strength. The material hardens with the increase in the test temperature: its tensile strength in the circumferential direction increases by a factor of 3 at a temperature of 3000°C, and the elastic modulus increases by a factor of 1.2 in the range of 1000–2000°C; however, with a further increase in the test temperature, it begins to decrease, and at a temperature of 3000°C, it is 0.3 of its value at room temperature.