High hardness, high strength, light weight, high chemical resistance, high temperature resistance and low thermal expansion
Each carbon fiber is composed of thousands of even smaller carbon fibers, about 5 to 8 microns in diameter, almost entirely made of carbon.
At the atomic level, carbon fibers are very similar to graphite, consisting of layers of carbon atoms arranged in a hexagonal pattern (graphene flakes). The difference between the two lies in the way the layers are connected.
Graphite is a crystalline structure, and its interlayer connections are loose, while carbon fiber is not a crystalline structure, and the interlayer connections are irregular. This prevents slippage and increases material strength.
Generally, the density of carbon fiber is 1750 kg/m3. The thermal conductivity is high but the electrical conductivity is low, and the specific heat capacity of carbon fiber is also lower than that of copper. When heated, the carbon fibers become thicker and shorter. Although the natural color of carbon fiber is black, it can be dyed a different color.