a forge that can reach and maintain 2400 C

[Geninji]

im seeking to make a personal forge that can reach and maintain 2400c temp to melt aluminum oxide. im not sure what materials can withstand this heat and have been looking at quartz and graphite materials but not sure if im going in the right direction and am looking for some sound advice. the fuel i would prefer is hydrogen but im very open to suggestions that are enviroment friendly.

[Frazer]

Out of curiosity, why are you trying to melt aluminum oxide?

To state the obvious, ~4300F is extremely hot. I would hesitate to call a chamber capable of withstanding those temperatures a forge...

[Geninji]

im curious if we can bring synthetic ruby & sapphire making into our homes at a reasonable rate to allow more people to make them and further reduce our need to mine them and provide at home jobs you can do at your own pace.

[Frazer]

I don't know anything about making synthetic rubies/sapphires... I can tell you that making something capable of withstanding those temperatures is going to be cost prohibitive for most people and certainly not safe to play around with at home...

[Geninji]

all the same nothing ventured nothing gained and if you dont have any adivice thats fine but im still gonna ask around and try anyway. thank you for the response.

[ThomasPowers]

You can make ruby using a fairly cheap arc welder and graphite crucibles; heating with hydrogen would be quite unsafe for most home folks due to it's characteristics and very expensive!

My old lincoln tombstone welder cost me US$40; I've found graphite for free.  Just buying a regulator for a hydrogen furnace would be several times that cost!

[Frosty]

You MIGHT be able to make a furnace liner to withstand those kinds of temperatures with sintered zirconia but the manufacture would be crazy expensive. 

Synthetic ruby and sapphire is pretty cheap, even gem quality. A hydrogen fired furnace on the other hand is again crazy expensive. 

Where have you researched the concept? Asking 50,000 random blacksmiths in 150 countries around the world is like walking a crowded street asking for extremely technically demanding advice. There's a good chance someone here knows enough to point you in the right direction but chances are they will be drowned out by wild ideas from folks who know nothing at all.

Frosty The Lucky.

[George N. M.]

I don 't want to be  a nay sayer BUT you are dealing with very high temperatures and a difficult fuel.  The two of them together may make for a dangerous situation.  Making synthetic corundum has been around for almost 200 years and is pretty much an industrial process.  I suspect that attempts have been made to scale down the process but there are things which do not lend themselves to scaling up or down very well.

Also, using H2 as a fuel presents its own problems.  It is a not particularly energy dense fuel which means you need to have a lot more volume for the same heat content.  It can have some interesting chemical interactions, particularly with metals, that you do not see with other fuel gases.

Good luck but be aware that you are dealing with things that can result in life changing injuries or removing yourself from the gene pool.  BE CAREFUL!  Approach this idea and project very cautiously and don't be afraid to back off if it starts to feel unsafe.  It is your decision on how to proceed but not forget the impact a mis-step could have on your family or neighbors.

"By hammer and hand all arts do stand."

[11xray]

I just want to say that I learned from this post, and appreciate the OP and commenters that contributed.