How to Care Alumina Ceramic Crucible

by Redthermo - 2018-11-08

Alumina ceramic crucible is widely used in the experimental analysis for its excellent performance, and satisfactory lifespan. However, to ensure the performance and lifespan of a crucible, it is very important to hand, operate and maintain it correctly, so i/n the current article, a care guideline of alumina ceramic crucible will be introduced for users.

1.Checking crucible for crack or damaged when received

Although crucible is fabricated with strict quality control and carefully packed, however very occasional damage may still happen during transportation. When crucibles are received, it’s necessary to inspect them carefully for cracks so as to avoid using a damaged one. If any of them are damaged during transportation, then contact the supplier for replacement.

2.Handling crucible with care

Never stack crucible with another one, since which may lead to cracking. Alumina crucible is fragile, so it’s necessary to handle them carefully.

3. Install crucible correctly

It is recommended to keep at least a 25mm distance from the heating source. Without adequate space between crucible and top and sides of the furnace, the crucible expands during the heating process, which may lead to cracking.

Make sure that the alumina ceramic crucible is completely dried before use. If it’s still wet, let it dry naturally or in a dryer at a low drying process.

Do not load too many materials in alumina ceramic crucible, which will increase the possibility of uneven heating.

4.Prevent thermal shock
For large-sized crucible, preheating is necessary to overcome the possible cracking due to thermal shock. It’s recommended to place the crucible on top of a substrate plate of the same material to reduce the risk of thermal shock, and a heating rate of 150°C/hour is recommended so that the crucibles can be evenly heated.

Lower the temperature as gradually as possible when finished using, and keep the cooling down rate at half of the heating rate, also be noted that heated alumina products contact with a cold surface should be avoided.

5. Do not exceed the maximum temperature limit

Every crucible has a maximum temperature limit depending on the material. Exceeding the maximum temperature will damage the crucible, so it is important to control the temperature of crucible carefully. For alumina ceramic crucibles, the maximum temperature limit is 1750°C

6. Use for eutectic compound treatment cautiously

Although 99.7 % Al2O3 does not react with most acids, chemicals or reagents, it may form low-temperature eutectic compounds with the element of Bismuth, Lead, Silicon, Tin, Antimony and rare earth. So note that do not use the alumina ceramic crucible for the heat treatment of the eutectic compound.

7. Ensure the right crucible is selected as a requirement.
Ensure that the right crucible, especially the right size and shape are correctly chosen for application to maximize its life span and performance.