Any recopies for 5000 degree refractory in steel making?

[Glenn]

J. Bennett
What ever you do, DO NOT go to IForgeIron.com > Lessons in Metalworking > Blacksmithing > LB0008 Reference material or LB0008.0001 Reference Material. There are over 100 on line blacksmithing and metalworking books behind those two links. More books and links are added as they become available, and the list keeps growing.

After catching up on your reading (grin), if you have questions, just ask.

[J. Bennett]

Wow.
Thanks to all the people who put the hard work into that. Great resource.

[RainsFire]

Something I dont understand, (theres alot of em..) is why cant we use a metal with a higher melting point to smelt the other one in? Like smelting bronze in a steel crucible.. would it contaminate the metals produced?

Oh, and where in oregon are you located? I'm in the corvallis/philomath area..

[J. Bennett]

That's a good question, but a very complicated answer. keep in mind I'm a backyard metallurgist, so take everything I say with a grain..
In alloy making, melting points are only for reference. You can alloy such and such a metal, say with a 4000F melting point, into molten iron @ 3300F. Why? It's called, well I actually don't know what it's called, but I call it the flux effect.

Just like molten flux can destroy a forge lining, several hundred degrees below it's melting point.

I would never use any metal crucibles to hold any other molten metals..
Although you can drastically reduce the melting point of alumina, and hold the liquid in a platinum crucible. Alumina, aluminum oxide, has a higher melting point than platinum, but the flux changes that. The making of Ramaura Cultured Rubies

I live in rural St. Paul, next to Champoeg.

[RainsFire]

ha, ya.. I dont get it you're definately leagues ahead of my understanding of metallurgy..
good luck on your experimentations!
and you're the same person from D-foggs site right? with the star chamber forge..
nice seeing you here!

[Ice Czar]

Originally Posted by RainsFire

is why cant we use a metal with a higher melting point to smelt the other one in? Like smelting bronze in a steel crucible

actually we do that all the time...sort of
1. its easier to form a refractory than to fabricate a metal container \ refractory is generally backed up by a metal container, the refractory being sacrificial

2. most refractories contain metal, or more commonly metal oxides, aluminium, magnesium, chromium ect

3. unoxidized metals at a high rate of temperature will tend to oxidize, from air, trapped gases, oxides in the melt ect

4. the overall rate of chemical activity (whatever it is) ramps up with temperature, its known as the Arrhenius equation and forms the basis of most time to failure calculations, everything from computer chips to bearings

The general rule of thumb, without solving the equation, is that for every 10°C increase in temperature the rate of reaction doubles

5. Employing metal oxides instead of metal generally makes the sacrificial barrier more stable since its already oxidized and its already undergone that particular reaction which is likely to alter the chemical bonds with other (typically) minerals and oxides (silica for instance)

6 you can and people do melt in metal containers, but generally unless they are cheaply had, a sacrificial refractory lining makes much more sense

[J. Bennett]

There ya go. Much better answer.
I just do this stuff by the seat of my pants.

Speaking of oxides.. I want some bulk, niobium oxide. I have never seen a more heat resistant material in my life! If you add niobium to a melt, make sure it's free of all oxide. it will totally wreck a melt otherwise.

[Ice Czar]

Originally Posted by J. Bennett

Speaking of oxides.. I want some bulk, niobium oxide. I have never seen a more heat resistant material in my life! If you add niobium to a melt, make sure it's free of all oxide. it will totally wreck a melt otherwise.

pretty too

hmmm... I see reference to an aluminothermic reaction with nobium pentoxide
you want it for the alloy or the refractory?

(the link of course is for others to keep on track)

[J. Bennett]

Funny you should mention niobium oxide as a reactant. Oxides can be either, or both. I can make a refractory from aluminum oxide, but aluminum is the main engine that fires the candle...
Experience and a a touch of chutzpahs is all that's needed.

BTW, WHO ARE YOU? A blacksmith that knows the intimacy of fire, or some master at Google-fu?

[J. Bennett]

Originally Posted by RainsFire

ha, ya.. I dont get it you're definately leagues ahead of my understanding of metallurgy..
good luck on your experimentations!
and you're the same person from D-foggs site right? with the star chamber forge..
nice seeing you here!

Yep. That's me.
The star chamber works better than expected.
Don't understand the whole Theology, but what ever works..