SSIC bearing advantage
In terms of mechanical properties, the relative density and tensile strength of hot-pressed and hot isostatically pressed silicon carbide are higher, and the reaction sintering is relatively low. However, the mechanical properties of silicon carbide ceramics can also be adjusted by the ratio of additives in the sintering.
In terms of corrosion resistance, pressureless sintering, hot press sintering and reactive sintering of silicon carbide are well tolerant to common acids and bases, but reactive SiC has poor corrosion resistance to hydrofluoric acid, strong bases, and phosphoric acid. In terms of temperature resistance, when the temperature is lower than 1000°C, the tensile strength of several shaped silicon carbides are similar, but when the temperature reaches or exceeds 1400°C, the tensile strength of the reaction-sintered silicon carbide sharply decreases. The main reason is that there are many unreacted free silicon monoliths in the reaction-sintered silicon carbide. When the temperature exceeds 1400 degrees Celsius, the activity of silicon monolith increases, and the intergranular structure is destroyed, resulting in a decrease in tensile strength. Compared to pressureless sintered silicon carbide and hot isostatic pressed silicon carbide, their high temperature resistance is mainly affected by the types of additives during molding.
In general, the overall performance of pressureless sintered silicon carbide ceramics is higher than that of reactive sintered silicon carbide, but lower than that of hot-pressed and hot isostatically pressed silicon carbide.
The silicon carbide materials used in fluoroplastic magnetic pumps and stainless steel magnetic pumps are primarily reaction-sintered silicon carbide and pressureless sintered silicon carbide. Mainly made into a magnetic pump in the pump static ring, rotor shaft, impeller sleeve, isolation sleeve bearings and other major products. The role is to play the role of grinding, special transfer magnetic torque.
In general, the corrosion resistance of reaction-sintered silicon carbide is good, and the tensile strength is also sufficient. However, in some special working media, it is necessary to pressurelessly sinter silicon carbide materials such as caustic soda, phosphoric acid, boric acid, and hydrofluoric acid. The reason is because reactive silicon carbide contains silicon and other impurities in the free state. These impurities cannot withstand the corrosion of the above medium. Therefore, after these impurities are corroded, the main structure will be damaged, the surface finish will be damaged, and the magnetic force will be affected Pump life.