In terms of manufacturing methods, the fusion method and the chemical method (colloid method) coexist and develop simultaneously to meet the needs of different types of uses.
(1) Melting method, commonly used in the production of amorphous (glassy) fibers (small cross-sectional area, production of short fibers), which has low technical content, low production costs, and a wide range of products, mainly used in industrial kilns Basic material in refractory and heat insulation applications of furnaces and heating devices.
(2) The chemical method is used to produce polycrystalline fibers. This method has high technical content, high production cost and high added value, but the products are still few. It is mainly used for refractory heat insulation of high temperature industrial furnaces above 1300C and reinforcement materials in cutting-edge technical fields such as aerospace, aviation, and nuclear energy.
The fiber-forming process of glassy refractory fiber is to use high-temperature melt blowing and centrifugal spinning method. There are many production methods and processes for continuous fiber and polycrystalline refractory fiber. At present, various new production methods and processes are still being tested. The applied processes include:
(1) Wire drawing method (to obtain continuous fibers), put the melt or spinning sol into a crucible made of platinum or other materials, and use heating or other methods to make it have the viscosity required for wire drawing. The liquid material is pulled out from the small hole on the bushing of the crucible, and then stretched at a high speed to obtain the fiber with the required diameter. Fibers with different diameters can be obtained by adjusting the viscosity, the diameter of the bushing hole and the drawing speed.