Is it possible to sinter "alumina, Al2O3" at 1200-1300 degree C?

The short answer is yes, but what type of Al2O3 do you want to make?

90%? What applications will it be used for? Ultimately mechanical, electrical, creep resistance and chemical resistance can all be dramatically affected by the flux and/or sintering aid added and the type of alumina being used in the body. Gregg

Hi Gregg,

Actually I want to work with high-density 99% alumina for crucible (?) or milling balls. What I concern is I don't want to add flux in the alumina. With low sintering temperature, however, I am sceptical about the density of the result. I may have to use an isostatic press but would this method will help the alumina to yield 100% density?

Pom

I worked with an ultra-fine high purity (99% + MgO) specialty alumina several years back that sintered to high density at 1300C. I thought it was a Baikowski alumina, but it has been a while. The material was rather pricy if I remember correctly. I work with aluminas quite frequently so this sinterability is quite unique, but you just might be able to find a decent nanopowder to work with. If I can remember anymore details I will pass them your way.

What applications are the crucibles for? - generic high density or applications with a lot of thermal shock? . You can try using some fine alumina's with beohmite additions, but the material may be hard to process. ceraboy's reply was right on the mark - but it may take some searching and the raw material cost will go up. I think it is possible, but you'll have to do some development work with both your processing and materials. (or higher a consultant who can set your process up - I can't think of anyone at the moment, but I can get some names for you if you'd like) Both processing and materials will play a role in the finished product. I think the best approach is:

1. Bring someone in who can look at your capabilities and give some guidance.
2. If you have capable people there, do some r&D
3. Buy a high temperature kiln

Gregg