Ceramic fiber is a kind of fibrous lightweight refractory materials and the main chemical composition of it is aluminum silicate. According to its mineral composition, it can be divided into two kinds: glass fiber and Polycrystalline fiber.
Glass fiber material is formed by molten liquid flow in the cooling of an amorphous solid fiber; Colloid injection is usually used to form fiber, through high temperature calcination, polycrystalline fiber is formed.
Ceramic fiber is widely used in all kinds of furnaces of high temperature resistant and heat-insulated materials. Due to its bulk density is much lower than other refractory material, thermal storage is little, and heat insulation effect is obvious. As lining material, it can greatly reduce the energy loss thermal kiln. In the aspect of energy saving, it has brought a revolution for furnaces. On the other hand, its application technology and method also have brought a revolution for thermal furnace masonry.
1. Current situation of application
Ceramic fiber first appeared in 1941, the Barb Wilcox Company uses natural kaolin clay, through the electric arc furnace melting injection, to manufacture fibers. In the late 1940s, the two companies produced series of aluminium silicate fibre, and applied them in the aviation industry for the first time; In the 1960s, the United States developed a variety of ceramic fiber products, and used in wall lining of industrial furnace. In the 1970 s, ceramic fiber started be Started be produced and used in China and its application technology got rapid promotion in the 1980s, but the temperature used mainly under 1000 ℃. Application technology at that time is relatively simple and laggard. After entering the 1990s, with the application of containing zirconium fiber and polycrystalline alumina fiber, service temperature reached to 1000 ℃ ~ 1400 ℃. However, due to the poor product quality and laggard application technology, application field and application way have been limited. There are some examples: Polycrystalline alumina fiber cannot be made into fiber blanket; Product specification sheet is given priority to loose cotton, fiber blocks; Although insulating temperature of electrical appliances has increased, because of the poor intensity, limiting the scope of use and shortening the service life.
Containing zirconium fiber is a widely?applied and low-cost aluminum silicate fiber, which produced by melting. It can be used to build the heat-surface whole fibers liner of various thermal furnace. In terms of quality and application and development, current domestic products are still relatively backward. Now chrome fiber appeared in the overseas, its service temperature is higher than containing zirconium fiber, China hasn’t report this aspect.
2. Categories and application
Ceramic fiber is mainly classified into: ordinary aluminum silicate fiber, high aluminum silicate fiber, aluminum silicate fiber (Cr2O3, ZrO2 or B2O3), polycrystalline alumina fiber and polycrystalline mullite fiber, etc. In recent years, foreign countries has successfully developed or is developing some new types of ceramic fiber, such as: forsterite fiber, ceramic fiber (SiO2 - CaO - department of MgO style and Al2O3 - CaO department), etc. The shape of the ceramic fiber products mainly include: ceramic fiber cotton, felt, blanket, modules, paper, cloth, tape, rope, etc.
Ceramic fiber blanket (fiber module): it often use the manufacturing process of self fluxing or melting and swing to made jilt silk long fiber, through stabbing by the double needle, making the fiber woven. It can used directly as the heat surface flame, gathering fire-resistant, heat insulation, heat preservation into an organic whole. It can be used for a long time in neutral, oxidizing and reducing atmosphere, still maintaining good strength and toughness. The fiber carpet fiber module made by this way contains no binder, has good thermal stability, widely used in petrochemical, metallurgy, electric power and other heat preservation and heat resisting field.
Ceramic fiber board: it is made from the ceramic fiber and binder, additives, after pulping, molding, curing and drying process. Ceramic fiber board has good flexibility, easy cutting, high strength, is a kind of low thermal conductivity and low heat storage of the new energy-saving environmental protection products. It is widely used in the walls and roofs backing of various types of heating equipment, belonging to heavy refractory materials.
Ceramic fiber cloth, belt: it is mainly used in fire doors, heat insulation of industrial furnace and heat insulation of pipes and containers.
Ceramic fiber rope: it is mainly used in the expansion joints of various industrial kilns, the winding insulation of high temperature pipe, heat insulation of the connection of steel structure, etc.