Chemicals that can corrode aluminum silicate ceramic fiber include fluorine, fluoride, vanadium and other heavy metals, phosphoric acid, strong alkaline, etc.

     1. Fluorine and fluoride. There is no doubt that fluoride is the most corrosive to aluminum silicate ceramic fiber. Under 100 ℃, the reaction of fluoride and water with aluminum silicate ceramic fiber will cause great damage to the fiber structure. Even at a low concentration, hydrofluoric acid will react with aluminum oxide to form AIF, AIF3 and H20, causing serious damage to the fiber structure. Hydrofluoric acid reacts most easily with SiO2. At a lower temperature (below 980 ℃), the fluorine rich environment may promote the low temperature recrystallization, which may lead to slight damage to the fiber structure. At the temperature where a large amount of recrystallization occurs, fluorine may form reactants on the fiber surface, thus causing changes in the fiber structure and obviously forming a thin hard shell layer on the fiber surface. Fluorine reacts with all aluminum silicate materials, including mullite. After the reaction with fluorine, the reactants often vaporize, making it difficult to determine the cause of the damage of aluminum silicate ceramic fiber.