Refractory Materials Improve Plasticity

Raw material preparation including raw material selection, calcination, fine crushing and purification treatment. The purity of raw materials used in the production of pure oxide refractories is more than 99%.Refractory Materials 

At the same time, the types and quantities of impurities contained in the raw materials have different limitations depending on the use of the product. The raw material is prepared to remove volatile substances in the material, to improve the purity of raw materials, to promote the densification of raw materials, to reduce the shrinkage of the billet during sintering, to form a stable crystalline phase, and to reduce the change of the stress or volume caused by the transformation of the billet during sintering.Refractory Materials

When raw material is burnt, it is necessary to control the calcination temperature. The calcination temperature is too low to reach the aim of burning, so it is difficult for the billet to be sintered again because of the recrystallization. The material can also be melted in an arc furnace, cooled and solidified and then crushed and applied. The raw material is of good chemical stability, the billet is reduced in sintering, but the cost is higher, the sintering of the billet is difficult. The pure oxide refractories require the fine powder material to be formed, the fine powder particle size generally is several microns to dozens of microns.Refractory Materials

The fine powder can improve the plasticity of the material, facilitate the forming, and make the raw billet compact. Powder particles small, large specific surface area, surface can be increased, conducive to sintering. Crushing equipment can be used ball mill, vibration grinder and airflow grinding machine. The raw materials may be introduced into various impurities during the preparation process and should be purified. Purification treatment methods are washed, acid washing, solvent washing and magnetic separation.Refractory Materials

At a certain temperature to maintain the powder in the liquid paraffin suspension, and then pressure to the suspension body into the metal mold, rapid solidification molding. Isostatic pressing method. First, the powder is installed in the elastic 409-sex rubber or plastic mold bag, and then pressurized in the high-pressure liquid cylinder molding. Casting method. After melting the raw material in the arc furnace, the melt is directly molded into the refractory model and then processed by annealing and machining.Refractory Materials