What is the difference between alumina ceramics and ordinary ceramics?
Alumina ceramics are divided into two types: high purity type and common type.
High-purity alumina ceramics are ceramic materials with Al2O3 content above 99.9%. Due to its sintering temperature as high as 1650 -- 1990℃ and transmission wavelength of 1 -- 6 m, fused glass is generally made to replace platinum crucibles. Its light transmittance and alkali resistance to metal corrosion are used as sodium lamp tube. In the electronics industry, it can be used as integrated electric subgrade board and high frequency insulation material.
Ordinary alumina ceramic system is divided into 99 porcelain, 95 porcelain, 90 porcelain, 85 porcelain and other varieties according to the content of Al2O3, sometimes Al2O3 content in 80% or 75% also classified as ordinary alumina ceramic series. Among them, 99 alumina ceramic materials are used for making high temperature crucibles, fireproof tubes and special wear-resistant materials, such as ceramic bearings, ceramic seals and water valve plates. Alumina ceramics are mainly used as corrosion-resistant and wear-resisting parts. Because part of talc is often mixed in 85 porcelain, the electrical property and mechanical strength are improved. It can be sealed with molybdenum, niobium, tantalum and other metals, and some of them are used as electrical vacuum devices.
The forming methods of alumina ceramic products include dry pressing, grouting, extrusion, cold isostatic pressing, injection, flow casting, hot pressing and hot isostatic pressing, etc. In recent years, some molding technologies have been developed, such as filter press molding, direct solidification injection molding, gel injection molding, centrifugal grouting molding and free solid molding. Products with different shapes, sizes, complex shapes and precision require different forming methods.
1. The hardness
The hardness of rockwell is hRA80-90, which is second only to diamond, and far exceeds the wear resistance of wear-resisting steel and stainless steel.
2. Excellent wear resistance
The wear resistance is 266 times that of manganese steel and 171.5 times that of high chromium cast iron. According to our customer tracking survey over the past ten years, the service life of the equipment can be extended at least ten times under the same working condition.
3. Light weight
Its density is 3.5g/cm3, only half that of steel, which can greatly reduce the equipment load.
