Natural Sources and Preparation of Powders

Aluminum is one of the most abundant elements on Earth and, in its oxidized form, is a constituent of most common minerals. Pure aluminum oxide is relatively rare, but may be found in the form of single crystal, when it is used as a gemstone in its colorless (sapphire) or red (ruby, due to the admixing of chromium) modifications. 

Mekmg point Thermal conductivily Thermal expansion coefficient (25-1000 °C) 2053 C 25 C 1000 C Parallel with c Perpendicular to c 40Wmir lOWmK 8.8.10 K 7.9.10 K  

Density Young s modulus 3.98gcm Parallel with c Perpendicular to c 435 GPa 386 GPa 

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