Alumina ceramic screw, bolt and nuts belong to ceramic fasteners. Alumina ceramics are ceramic materials based on alumina (Al2O3) for thick film integrated circuits. Alumina ceramics have good conductivity, mechanical strength and high temperature resistance. It should be noted that ultrasonic cleaning is required. Alumina ceramics is a versatile ceramic. Because of its superior performance, it has been widely used in modern society, satisfying the needs of daily use and special performance.

Alumina ceramics are classified into high-purity type and ordinary type.
The high-purity alumina ceramics have a Al2O3 content of 99.9% or more. Since the sintering temperature is as high as 1650-1990 ° C and the transmission wavelength is 1 to 6 μm, the molten glass is generally used to replace the platinum crucible; Sexual and alkali-resistant metal corrosion is used as a sodium lamp; it can be used as an integrated circuit substrate and high-frequency insulation material in the electronics industry.

Ordinary alumina ceramics are classified into 99 porcelain, 95 porcelain, 90 porcelain, 85 porcelain, etc. according to the content of Al2O3. Sometimes the content of Al2O3 is 80% or 75%, which is also classified into ordinary alumina ceramic series. Among them, 99 alumina ceramic materials are used to make high temperature crucibles, refractory furnace tubes and special wear-resistant materials, such as ceramic bearings, ceramic seals and water valve sheets; 95 alumina ceramics are mainly used as corrosion-resistant and wear-resistant parts; In addition, due to the incorporation of part of talc, the electrical properties and mechanical strength are improved, and it can be sealed with metals such as molybdenum, niobium and tantalum, and some are used as electric vacuum device devices.