HENAN TIANMA THE NEW MATERIAL SHARES CO.,LTD.

HENAN TIANMA THE NEW MATERIAL SHARES CO.,LTD.

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HENAN TIANMA THE NEW MATERIAL SHARES CO.,LTD.
  • Tel:+86-371-68942898 13938253542 13523012188
  • Fax:+86-371-68942899
  • Address:No.25, Anyang Road, Shangjie District, Zhengzhou, China
  • E-mail:zztmwfgs158@sina.com
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Alumina Process and Phases

        Aluminum oxide, also named alumina, is a chemical compound of aluminium and oxygen with the chemical formula Al2O3. It has widespread applications including spark plugs, tap washers, pump seals, electronic substrates, grinding media, abrasion resistant tiles, cutting tools, bioceramics, (hip-joints), body armour, laboratory ware and wear parts for the textile and paper industries. Very large tonnages are also used in the manufacture of monolithic and brick refractories. It is also used mixed with other materials such as flake graphite where even more severe applications are envisaged, such as pouring spouts and sliding gate valves. Alumina is the most widely used oxide ceramic material. It occurs naturally as the mineral corundum and, with minor traces of chromium and cobalt, as the minerals ruby and sapphire, respectively. In its hydrated form it also occurs as the rock bauxite. Because Alumina is of such great importance in our chemical industry, Tianma will introduce the alumina producing process and forms as follows.
Alumina Process:        
        Most of the aluminium oxide produced commercially is obtained by the calcination of aluminium hydroxide (frequently termed alumina trihydrate or ATH).  The aluminium hydroxide is virtually all made by the Bayer Process. This involves the digestion of bauxite in caustic soda and the subsequent precipitation of aluminium hydroxide by the addition of fine seed crystals of aluminium hydroxide.
Alumina Phases:
        Aluminium oxide exists in many forms, α, χ, η, δ, κ, θ, γ, ρ; these arise during the heat treatment of aluminium hydroxide or aluminium oxy hydroxide.  The most thermodynamically stable form is α-aluminium oxide.