The use temperature of boron nitride ceramic crucible under vacuum is 1800 degrees, and the use temperature under atmospheric protection is 2100 degrees. Nitrogen or argon atmosphere is best used and has the longest life. The boron nitride crucible is strong against thermal shock. It does not crack when quenched at 1500 degrees. It is kept in a 1000-degree furnace for 20 minutes and taken out to blow and quench for hundreds of consecutive times without cracking.
Precautions for use:
1 The use temperature in air should not exceed 1000 degrees, and the surface of boron nitride that exceeds 1000 degrees will oxidize and peel off when it comes into contact with oxygen.
2 Boron nitride is easy to absorb moisture. The crucible cannot be stored in a wet area and cannot be washed with water. It can be directly wiped off with sandpaper or with alcohol.
3 Application direction of boron nitride crucible
[available materials]:
1. Ferrous metals: iron, copper, aluminum, nickel, magnesium, bismuth, zinc, etc., alloy FE-CO-NI-SI CO-ZR-NB
2. Not at room temperature Reacts with water and acids. Boiled with water and slowly hydrolyzed to produce boric acid and ammonia
3. Rare earth, nitride
[unavailable materials]:
1. Antimony trioxide, chromium oxychloride, molybdenum trioxide, arsenic trioxide, titanium carbide, etc. 2. High-lead glass The glaze melted in the air at 800-950 degrees will attack BN, but there is no reaction under the protection of nitrogen or inert gas. 3. Boron phosphate erodes boron nitride in nitrogen at 1400 degrees, and reacts with hot concentrated or molten alkali and hot chlorine gas.
