Alumina is a chemically strong ionized material, with high melting point hardness and high chemical stability, especially at high temperatures, it can maintain high hardness and strength. It is widely used in metallurgy, machinery Chemical industry, electronics, medicine, aviation and national defense. [url=https://www.hslabrasive.com/products/fused-alumina/]wholesale aluminium oxide[/url] Due to the ultra-micronization of alumina powder, its surface electronic structure and crystal structure have changed, resulting in surface effects, small size effects, and quantum effects that macroscopic objects do not have. Effect and macroscopic quantum tunneling effect; while aluminum oxide powder is the main raw material for the production of corundum (white corundum, brown corundum), here is a brief introduction to the crystal type of Al2O3?

The crystal forms of Al2O3 are: a, y, η, δ, day, K, x, etc. When the external conditions change, the crystal form changes. In the variants of AI2O3, since the oxygen in a-AI2O3 (density 3.99g/cm3) is the most densely packed, only 0(-AI2O3 (corundum) is stable, and other crystal forms are unstable. Will be transformed into a-AI2O3.

In addition to corundum, the common crystal type of AI2O3 should be y-AI2O3, γ-AI2O3 has a spinel structure, but in its structure, some tetrahedral voids are not filled, so the density of y-Al2O3 (3.65g/ cm3) is smaller than corundum. When Al(OH)3 is heated and dehydrated, y-Al2O3 is formed at about 450°, and γ-AI2O3 is heated to a higher temperature to transform into corundum. However, the conversion speed is relatively fast when the transformation is more than 1000?.

Some other unstable crystal forms of alumina are also formed under different conditions when AI(OH)3 is heated and dehydrated. ρ-Al2O3 is amorphous, but some people think it is a transition state between amorphous and crystalline. Since ρ-Al2O3 is a form that can spontaneously hydrate at room temperature among the various forms of AI2O3, it can be used as a cementing agent for refractory castables, so it has received attention in recent years.[url=https://www.hslabrasive.com/]https://www.hslabrasive.com[/url]