Looking for 6000 deg refractory 1

[Greenleader]

Hello.
I am looking for a refractory that can withstand up to 6000 F, to hold large,(12 pound charge), thermit reactions.

I prefer something I can shape myself.
Thanks.

 

[unclesyd]

Here are several leads on the thermite process. This is a dangerous do it yourself process for a first timer. Essentially there isn’t any material that will hold a thermite reaction. The process of making a crucible for thermite or molten metal has to be undertaken with the greatest of care. Any moisture or water of hydration left in the crucible materials is an horrible accident waiting to happen. The procedure now is to use a one shot crucible or a mold like the Cad Weld process.
The Lindsay site has a book on crucibles as well as the thermite book.

http://www.erico.com/products/CadweldPlus.asp

http://www.lindsaybks.com/bks4/thermit/index.html

http://www.stanley-hydraulic-tools.com/Railroad/thermite.htm

 

[Greenleader]

Thanks for those links unclesyd. Also for the safety tips.
I've made a few runs using a 5000 F rated furnace cement, but it takes a beating and needs repair after each run. The secondary crucible is the problem. I have to hold the molten charge, about 1 to 4 pounds, at heat, without damage to the refractory, or uptake of refractory in the ingot.

Also proper IR and UV protection is in order as it throws off a lot of radiation.

 

[unclesyd]

Is you reaction crucible cone shaped?
Is your secondary chamber acting as a float chamber for the slag? If the melt hits something as it's falling it will help the melt and slag separate.
What is your reaction crucible made from?

Are you coating your mold with anything?
An MgO wash will be helpful but will not completely protect the crucible. Again look out for moisture.

I'm try to find my information on additives for the slag that will make it more fluid to get a better float and also help lower the temperature.
There is some information about this process on the blacksmith and sword making net.

 

[Greenleader]

Thanks very much.
The reaction crucible is cyledrical, with cone shaped bottom.

I have a bunch of magnets under the mould crucible to possibly help with slag seperation. ????

The MgO is a good idea.
The blacksmith/sword maker is probably me

Thanks once again!