Special Properties Of Graphite
Mar 17, 2021
(1) High temperature resistance
The melting point of graphite is 3850±50°C. Even if it is burned by ultra-high temperature arc, the weight loss is very small, and the thermal expansion coefficient is also very small. The strength of graphite increases with the increase of temperature. At 2000°C, the strength of graphite doubles.
(2) Electrical and thermal conductivity
The conductivity of graphite is one hundred times higher than that of general non-metallic minerals. The thermal conductivity exceeds that of metal materials such as steel, iron, and lead. Thermal conductivity decreases with increasing temperature, even at extremely high temperatures, graphite becomes an insulator. Graphite can conduct electricity because each carbon atom in graphite forms only 3 covalent bonds with other carbon atoms, and each carbon atom still retains 1 free electron to transfer charge.
(3) Lubricity
The lubricating performance of graphite depends on the size of the graphite flakes. The larger the flakes, the smaller the friction coefficient and the better the lubricating performance.
