(1) High mechanical strength, the bending strength of alumina ceramic sintered products can reach 250MPa, hot-pressed products can reach 500MPa, and the strength can be maintained at high temperature up to 900°C
(2) High resistivity, good electrical insulation performance, room temperature resistivity 1015 Ωcm, dielectric strength 15 kV/mm
(3) High hardness, Mohs hardness 9
(4) High melting point, anti-corrosion, melting point 2050℃, can better resist corrosion of molten metals such as Be, Sr, Ni, Al, V, Ta, Mn, Fe, Co, etc. It also has high corrosion resistance of NaOH, glass and slag. Does not interact with Si, P, Sb, Bi in an inert atmosphere.
(5) Excellent chemical stability, many compounds of sulfides, phosphides, arsenides, chlorides, nitrides, bromides, iodides, oxides and sulfuric acid, hydrochloric acid, nitric acid, hydrofluoric acid are not oxidized Aluminum effect.
(6) Optical properties, the possibility of manufacturing light-transmitting materials (transparent porcelain Al2O3)
(7) Ionic conductivityDisadvantages of alumina ceramics
Alumina ceramics have low impact strength, poor heat resistance and cannot withstand sudden temperature changes. The impact resistance is low, it breaks easily and cannot withstand high pressure. At the same time, due to its low brittleness, its post-processing ability is very weak, which does not promote recycling, and basically can only be used once.Fields of application of alumina ceramics
Alumina ceramic is widely used in the field of lithium battery diaphragm coating and catalyst carrier because of its excellent physical and chemical properties.
(1) High demand for high purity ultrafine alumina in downstream processing
The main function of the lithium-ion battery separator is to separate the positive and negative electrodes of the battery to prevent short circuit, and its performance directly affects the capacity and safety of the battery. During battery use, if the temperature is too high, the diaphragm will melt and cause a short circuit. Diaphragm coating can improve the temperature resistance of the battery. Ultra-fine high purity alumina has good insulation and high temperature. It is a high-quality diaphragm coating material.
（2）Environmental issues are becoming more and more prominent, and the automotive catalyst market is huge
Automotive exhaust catalyst carrier is honeycomb cordierite ceramic, the surface is coated with aluminum oxide and alumina coating alloyed with rare earth elements. Because vehicle exhaust contains toxic carbon monoxide, nitrogen oxides, and hydrocarbons, gasoline-powered vehicles are typically equipped with vehicle exhaust aftertreatment devices. Alumina ceramic is widely used in the field of catalyst supports due to its excellent physical and chemical properties. With the advent of the new energy industry, especially new vehicles, cermet materials will inevitably make a big splash in the field of new energy due to their excellent physical and chemical properties.