Heating material: carbon fiber. Carbon fiber is a kind of raw material fiber with high carbon content (usually more than 90%), which is put in inert gas and treated by heat stable oxidation at 200-300 ℃, carbonization and graphitization at 1000-2000 ℃. According to different basic materials, PAN based carbon fiber can be divided into polyacrylonitrile (Pan), asphalt based carbon fiber and viscose based carbon fiber, in which PAN based carbon fiber accounts for 90% of the world's carbon fiber production..
Carbon fiber has the characteristics of high temperature resistance, abrasion resistance, conductivity, heat conduction and corrosion resistance. Its shape is anisotropic, soft and can be processed into all kinds of fabrics. Its specific gravity is small and it shows high strength along the fiber axis. Carbon fiber can be compounded with resin, metal, ceramic and other matrix to form a variety of composite materials, which can be used in aerospace, automobile, oil drilling, sports and medical equipment and other fields.
According to the different structure of heating body, it can be divided into two kinds: carbon fiber heating cable and carbon fiber heating film. The carbon fiber electrothermal film can be divided into the following two types according to the different production and processing processes: one is the non-uniform linear carbon fiber electrothermal film produced by directly using carbon fiber filament (small tow or large tow) as a part of warp or weft thread through the textile process; the other is the carbon fiber electrothermal paper formed by cutting the large tow of carbon fiber filament into short fiber through the papermaking process. The above-mentioned carbon fiber electric heating materials are covered with different insulating layers according to the requirements of different uses and insulation grades, which forms carbon fiber electric heating films of different insulating materials.