This article mainly talks about the properties and properties of alumina ceramic materials, and their advantages and disadvantages:
Alumina ceramics are divided into two types: high-purity and ordinary.
High-purity alumina ceramics are ceramic materials with an Al2O3 content of more than 99.9%. Since their sintering temperature reaches 1650–1990°C and the transmission wavelength is 1–6 µm, they are usually turned into molten glass. to replace platinum crucibles; Corrosion resistance to light and alkali metals, can be used as a sodium lamp; it can be used as an integrated circuit substrate and high frequency insulating material in the electronics industry.
Ordinary alumina ceramic is divided into 99 porcelain, 95 porcelain, 90 porcelain, 85 porcelain and other varieties according to Al2O3 content. Sometimes ceramics with 80% or 75% Al2O3 content are also classified as ordinary alumina ceramic series.
Among them, 99 alumina porcelain materials are used to make high-temperature crucible, refractory chimney and special wear-resistant materials such as ceramic bearings, ceramic seals and water valve plates, etc.; 95 alumina porcelain materials are mainly used for corrosion-resistant and wear-resistant parts; 85 porcelain is often mixed with some talc, which improves electrical properties and mechanical strength, and can be sealed with molybdenum, niobium, tantalum and other metals, and some are used in as an electric vacuum device.
It is estimated that everyone already knows about alumina ceramic materials. At present, alumina ceramic materials are widely used in our lives, so what are the advantages and disadvantages of alumina ceramic materials?
Advantages of alumina ceramics:
1. Aluminum oxide ceramic has excellent insulation, low loss at high frequency, but good insulation at high frequency;
2. Alumina ceramic has heat resistance, small thermal expansion coefficient, high mechanical strength and good thermal conductivity.
3. Aluminum oxide ceramic has the characteristics of chemical corrosion resistance and molten metal resistance.
4. Alumina ceramic is non-combustible, rustproof and durable, not easy to be damaged, and has excellent properties, incomparable with other organic and metal materials.
5. The wear resistance of alumina ceramics, but the hardness is the same as that of corundum, which can reach the ninth grade of Mohs hardness, and the wear resistance is comparable to the wear resistance of superhard alloys.
Properties of alumina ceramics:
1. High hardness
Alumina has been determined to have a Rockwell hardness of HRA80-90, a hardness second only to diamond, far surpassing the wear resistance of wear-resistant steel and stainless steel.
2. Excellent wear resistance
The wear resistance of alumina ceramics is 266 times higher than that of manganese steel and 171.5 times higher than that of high chromium cast iron, according to the Institute of Powder Metallurgy of the Central South Technological University. According to a survey of our customers over the past ten years, this can extend the life of the equipment by at least ten times under the same operating conditions.
The density of cermet material is 3.7~3.95g/cm³, which is only half of the density of steel, which can greatly reduce the load on the equipment.
4. Wide range of applications
On all mechanical equipment with high wear, such as coal conveying, material conveying system, grinding system, ash and dust removal system in thermal power, steel, smelting, machinery, coal, mining, chemical, cement, port and wharf enterprises and etc. You can choose different kinds of products according to different needs.
The above editor summarizes the advantages and disadvantages of alumina ceramic materials for everyone, hoping to be useful to everyone.