Tabular alumina is made by holding calcined alumina powder just below its 2040C fusion temperature to recrystallize the normally flat crystals into hexagonal, elongated tablet-shaped ones up to 400 microns in size. It is possible to convert near 100% of the crystals and achieve a high chemical purity. The new crystals maintain the same hardness and density and have much better thermal shock resistance.
Tabular aluminas are useful in ceramics, electrical insulators, dielectrics and refractory applications. They are available in sizes from around 40 mesh down to 325 mesh.
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