High temperature electrical insulating coatings can be classified into many types depending on their chemical composition. For example, boron nitride or aluminum oxide, or copper fluoride coatings on the surface of graphite conductors still have good electrical insulation properties up to 400 ℃. The enamel on the metal wire reaches 700 ℃, the phosphate based inorganic adhesive coating reaches 1000 ℃, and the plasma sprayed aluminum oxide coating maintains good electrical insulation performance at 1300 ℃. High temperature electrical insulating coatings have been widely used in power, electrical machinery, electrical appliances, electronics, aviation, atomic energy, space technology, and other fields.