1.Features
（1） Crucible with alumina content over 95% is called corundum crucible.
（2）Corundum Ceramic crucible is composed of porous fused alumina, which is firm and refractory.
（3） Corundum Ceramic Crucible is suitable for melting samples with some weakly basic substances such as anhydrous Na2C03 as flux, but not suitable for melting samples with strong alkaline substances such as Na 202 and NaOH and acid substances (such as K2S 207, etc.)
2. Index
Alumina crucible and corundum crucible index Non-expansion ceramic crucible is a new generation of products after clay, cordierite, quartz, and film-coated crucibles in China. Yixing Junteng refractory ceramics has long production of non-expansion ceramic crucibles. Corning's products imported from the United States are comparable, and are well received by users for their excellent performance such as high life span and low consumption. Crucible 1. Ultra low expansion coefficient, high thermal vibration stability...
Three, cleaning method
1. Acid bubbles: usually soaked with nitric acid for a long time; then washed with water
2. Drying, slowly heating up to 800℃ in high temperature furnace for 6 hours
3. Take it out after cooling and use it.
4. Remove impurities, convert insoluble materials into soluble nitrate and remove.
5. Removal of trace nitrate in the crucible (thermal decomposition method): Note that the heating rate must not be fast, otherwise the crucible will be skinned (fracture damage).
