How to Clean an Alumina Crucible?

Alumina crucible is also called corundum crucible. Shapes mainly include cylindrical, conical, arcuate, sagging and other shapes. The alumina crucible is of high purity and contains more 99% AL203.

Alumina Crucible Cleaning

1. Crucible cooling: Before you start cleaning, make sure, that the alumina crucible has cooled completely, to avoid burns.
2. Removing residues: Use plastic or metal tools, to gently scrape off the residue in the crucible, such as residual powder, carbide, etc.. Avoid using sharp objects, to avoid scratching the crucible.
3. Cleaning: Soak in nitric acid for a long time.
4. Dry humidity: Dry the alumina crucible before use, to prevent rupture, caused by water. When drying, it is usually dried at a temperature 200 degrees. Heat slowly until 800 degrees in a high temperature oven for 6 hours, and then cool, to use later.

Precautions when cleaning the corundum crucible

• avoid sudden changes in temperature: Before use, make sure, that the cleaned crucible is completely dry, and avoid sudden changes in temperature, so that thermal shock does not lead to the formation of cracks.
• Avoid sharp objects: Avoid using sharp objects when cleaning and scraping off residue., to avoid scratching the surface of the crucible.