Alumina ceramics are the most widely used and most productive ceramic materials in oxide ceramics. They are widely used in machinery, electronics and electricity, chemical engineering, medicine, architecture and other high-tech fields. Here briefly introduce the application of Al2O3 ceramics in the above six aspects.

1. Mechanical aspects

The bending strength of Al2O3 ceramic sintered products can reach 250MPa, and the hot-pressed products can reach 500MPa. The Mohs hardness of Al2O3 ceramics can reach 9, plus it has excellent wear resistance, so it is widely used in the manufacture of tools, valve balls, grinding wheels, ceramic nails, bearings, etc. Among them, Al2O3 ceramic tools and industrial valves are the most widely used .

1.1 Al2O3 ceramic cutter

The optimal cutting speed of Al2O3 ceramic tools is higher than that of general cemented carbide tools, which can greatly improve the cutting efficiency of different materials. With a lot of research by scientists, other components are added to form two phases or exist in the form of solid solution in Al2O3-based composite ceramics and whisker-reinforced ceramics. These technologies make up for the shortcomings of pure Al2O3 ceramics, thereby improving its cutting performance and durability.

1.2 Pure Al2O3 ceramic tool

Pure Al2O3 ceramic tools refer to high-purity Al2O3 ceramics containing only a small amount of oxides. In pure Al2O3 ceramics, ZrO2 can be added as a sintering aid to improve its fracture toughness. Pure Al2O3 ceramic tools have good high temperature performance and wear resistance, but have low bending strength and poor impact resistance. At present, they are increasingly replaced by various composite Al2O3 ceramic tools.

1.3 Composite Al2O3 ceramic tool

Al2O3-carbide ceramic tools are made by adding certain carbides to Al2O3 to improve its strength, wear resistance, impact resistance and high temperature performance. Due to the addition of metal, the connection strength between Al2O3 and carbide is improved, and the performance is improved. This type of ceramic tool is suitable for processing hardened steel, alloy steel, manganese steel, chilled cast iron, nickel-based and cobalt-based alloys, and non-metallic materials and so on.

1.4 Toughened Al2O3 ceramic tool

Toughening Al2O3 ceramic tools refers to adding toughening or reinforcing materials to the Al2O3 matrix. Currently commonly used toughening methods include: ZrO2 phase transformation toughening, whisker toughening, and second phase particle dispersion toughening.

2. Electronics/electricity

In terms of electronics and electricity, there are various Al2O3 ceramic base plates, substrates, ceramic membranes, transparent ceramics, and various Al2O3 ceramic electrical insulating ceramics, electronic materials, magnetic materials, etc., of which Al2O3 transparent ceramics and substrates are the most widely used.

2.1 Al2O3 transparent ceramic

Currently, transparent ceramics is an important frontier in the research and application of materials. As an emerging material, transparent ceramics, in addition to its wide range of light transmittance, also has a series of advantages such as high thermal conductivity, low electrical conductivity, high hardness, high strength, low dielectric constant and dielectric loss, wear resistance and good corrosion resistance.

2.2 Al2O3 ceramic substrate

Al2O3 ceramic substrates have excellent properties such as high mechanical strength, good insulation, and high light resistance, and are widely used in multilayer wiring ceramic substrates, thick film resistor, electronic packaging and high-density packaging substrates.

3. Chemical industry

In terms of chemical applications, Al2O3 ceramics also have a wide range of uses, such as Al2O3 ceramic chemical filler balls, inorganic microfiltration membranes, and corrosion-resistant coatings. Among them, Al2O3 ceramic membranes and coatings have been studied and applied the most.

3.1 Al2O3 ceramic membrane

The membranes are divided into organic polymer membranes and inorganic membranes. Compared with organic polymer membranes, ceramic membranes have the following characteristics:

(1) High temperature resistance and good thermal stability;

(2) High strength, will not be compressed under large pressure gradient operation, good mechanical properties;

(3) Good chemical stability, resistant to corrosion by strong acid and alkali solutions, organic solvents and chlorides, and not degraded by microorganisms;

(4) It can be used repeatedly, is easy to clean, and the pore size and pore size distribution are easy to control during preparation.

4. Medical

In medicine, Al2O3 is more used to make artificial bones, artificial joints, artificial teeth, etc. Al2O3 ceramics have excellent biocompatibility, biological inertness, physical and chemical stability, high hardness, and high wear resistance. It is an ideal material for preparing artificial bones and artificial joints. However, it has the same shortcomings as other ceramic materials, such as high brittleness, low fracture toughness, high machining technology difficulty, and complex technology, so further research and application are needed.

5. Construction/Sanitation/Ceramics

In building sanitary ceramics, products can be seen everywhere, such as Al2O3 ceramic lining bricks, grinding media, rollers, ceramic protection tubes and Al2O3 refractory materials. Among them, Al2O3 ball milling media is the most widely used.

6. Other aspects

Al2O3 ceramics is currently one of the most studied and widely used materials among new materials. In addition to the above applications, it is also widely used in other high-tech fields, such as aerospace, high-temperature industrial furnaces, and composite reinforcement.

Conclusion

Al2O3 ceramic material is one of the most widely used ceramic materials. Foreign research on Al2O3 materials started early, especially in high-tech fields such as machining, medicine, and aerospace.