Al2O3 Alumina ceramic
What is alumina ceramic material?
Alumina ceramics are a kind of alumina (Al₂O) as the main body of the ceramic material, according to its alumina purity can be divided into high purity type and common type two, the use is also different.
High purity alumina ceramics refer to those in which the content of
Al₂O₃ is more than 99.9%. Due to the sintering temperature of 1700℃ and
transmission wavelength of 1 ~ 6μm, they are generally made into molten
glass to replace the platinum crucible. Use its light transmission and
alkali metal corrosion resistance as sodium lamp tube; It can be used as
integrated circuit board and high frequency insulation material in the
electronics industry.
The common alumina ceramics are divided into 99 porcelain, 95 porcelain,
93 porcelain, 92 porcelain, 85 porcelain and other varieties according
to the content of Al₂O₃, which is mainly used in the field of industrial
anti-wear. Among them, 99 alumina porcelain materials are used to make
high temperature crucible, refractory furnace pipe and special
wear-resistant materials, such as ceramic bearings, ceramic seals and
water valves; 95 alumina porcelain is mainly used as corrosion
resistance and wear resistance parts; The 85 porcelain is often mixed
with talc to improve the electrical properties and mechanical strength,
and can be sealed with molybdenum, niobium, tantalum and other metals,
and some are used as electric vacuum devices.
Alumina ceramics are sintered by high-quality alumina powder, at 1700℃
high temperature, alumina will be converted into α alumina, forming a
special crystal structure, not only hardness exceeds RHA85, second only
to diamond, excellent wear resistance, far more than wear-resistant
steel, cast stone cast iron and so on. And the chemical properties of
αalumina are stable, can resist most acid and alkali corrosion, and its
high temperature resistance is also very strong, aluminum oxide ceramic
liner and aluminum oxide ceramic pipe are widely used in the field of
industrial anti-wear.