99.7% Al2O3, density 3.922g/cm3, hardness 9 (Mohs scale). Can be used up to 1700˚C, with excellent chemical resistance and mechanical strength.
All dimensions and capacities are nominal.
Notes on the care and use of Alumina Products
Alumina products are fragile, please avoid impacts during handling to prevent micro-cracks at the surface. Products with any micro-cracks should not be used.
Alumina should also be kept completely free of moisture and, if drying, please ensure that the temperature in the drying oven is increased slowly. Alumina is sensitive to thermal shock. Do not use alumina crucibles over naked flames, such as that from a bunsen burner - crucibles must be heated evenly using a furnace, oven etc.
Avoid overloading of crucibles to prevent uneven heating and ensure that the furnace chamber temperature increases gradually to prevent thermal shock (a rate of 150°C per hour for the first 1 to 1.5 hours is recommended, with maximum temperature achieved after 3 hours). When cooling, lower the temperature as gradually as possible. The cooling down rate is often half of the heating rate. If removing the crucibles from the furnace into room temperature to pour melted material, try to keep the process as short as possible. Once removed, avoid placing crucibles on any cold surfaces.