The properties of 99% alumina ceramics

99% alumina ceramic material hardness, high strength, low coefficient of expansion, and insulation, wear resistance, corrosion resistance, in machinery manufacturing, aerospace, precision instruments, petrochemical and other fields have a wide range of applications.

Alumina ceramic parts are usually formed by isostatic pressing sintering. Because sintering often brings deformation and shrinkage, further finishing is generally required to ensure the size and shape accuracy of parts.

However, alumina ceramic materials generally have large elastic modulus, high hardness, brittleness and strong crack sensitivity. Therefore, the machining difficulty is mainly reflected in the machining hardness and brittleness.

Processing hardness of alumina ceramics: AL203 mainly has α, β, γ three crystal morphology, among which α -Al203 crystal morphology is the most stable, at 1300℃ I3 and γ crystals almost completely transformed into α crystals.

In the crystal form of α -Al203, the atomic bonds formed by aluminum ion and oxygen ion are mostly covalent bonds, ionic bonds or their mixed bonds, so the interatomic binding energy is very high and has strong directivity.