Light weight, good thermal insulation performance, good thermal stability, good chemical stability, easy processing and convenient construction. It is neither wear-resistant nor collision-resistant, and cannot resist the erosion of high-speed air flow and molten slag.

Modules, including folding block, slicing block, Parrot block and vacuum forming block. Due to the different manufacturing methods and crystal structure of polycrystalline mullite fiber, its fiber length is short and its flexibility is poor. The polycrystalline fiber can not be applied on a large scale because it cannot be made into a large module. The polycrystalline fiber is mostly used for sticking blocks on the inner surface of castable or refractory brick furnace wall and furnace top. The use of polycrystalline fiber sticking blocks can effectively reduce the temperature of furnace outer wall and reduce the heat storage loss of furnace wall.