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Any recopies for 5000 degree refractory in steel making?


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5000 F?

what alloy are you melting that high?
Most steel will melt at 2500F (1370C)....



Um, well..
First, thanks for that awesome link. I really can use that. The MgO bricks are great! *kid in candy store*
As far as the temp requirements, well thats sort of my plane, so to speak. BTW, "Ice Czar" . Now that's ironic. :D;)
Thanks again Ice, for the resource! Jerry
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Well then.
Thermodynamics eh?
Ice and fire. Nice.
here is an mpg of my early steel making. A 10 pound charge of thermite..
It was too wide, and thus made a too large of a thermal mass. Melted clean through my 5000 furnace lining.

I have since learned how to tame the dragon. but try not to get cocky.
MOV01705.flv - Video - Photobucket - Video and Image Hosting
BTW, 6170 ain't no thang.. Back atcha

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High Carbon Steel Melts at Approximately 2600F and low carbon steel melts at 2800F Often cast steel is poured at a few hundred degrees hotter for adequate fluidity. This is why high carbon steel burns easier when forging than lower carbon steels.

I suggest going out on the web to learn of available refractories.

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what are you casting? or are you?

Low alloy refractory steel. Stuff that does not exists in the text books....yet

Ive been able to alloy a rhenium alloy, and other transition metals, with other refractory elements, via exothermic reaction.
I'm being coy because I have patent pending.
EDIT: R Funk, ther is no carbon in this steel. It makes for a higher playground..
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I'm being coy because I have patent pending.


one of the ten most expensive metals on earth known for its superconducting properties in some alloys patent pending? :P
a good refractory steel would be very useful around here

was actually looking for "wheel" "gear" "ingot" :P

have fun ;)

(its about time we had more alchemy in here)
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Boy, you ain't kidding.
Briefly, I chose rhenium because of it's unique properties. It's the only metal that is malleable from absolute zero, to it's melting point, which is quite high. Around 5200F!
The platinum group, can contribute to simple steel, above and beyond current paradigms.
Just like anything, all it takes is money...:mad:

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Hi Jerry. If you are interested in thermite, you may wish to read:

http://journalof911studies.com/volume/200704/JLobdillThermiteChemistryWTC.pdf

Especially interesting is Figure 3. Disregard all the non-thermodynamic stuff. The appendix is a great reference section for the temperature dependent heat capacities of the reactants. The iron phase transitions are neglected, and these will cause the calculations to be optimistic (pessimistic :D:o). But the error introduced by neglecting radiation and other mechanisms of heat loss is much higher.

I wonder that, with sufficient diluent in the form of low carbon steel/iron, you could decrease the temperature requirement of the refractory. The characteristic heat transfer time for small steel punchings or granules is probably on the order of a second, with the high radiative component.

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That has a lot of useful information.
T-mite is low tech, but after observing scores of runs, some up to 12 pounds, I know that there are a lot of complicated thermal dynamics going on.

I didn't like the sulfur/iron info though. I assumed the reaction got rid of all that nasty stuff.
As for the 5000 degree requirement, I put melt doors in the bottom and a very small tap hole. That way it gives the reaction some time to settle and separate. Consequently it sits on the refractory a while. I've weighed the iron afterwards, including all the "spatter" I could find. I find that during large runs, about 5% of the iron boils away. There is probably +- 2% as there might be a bit of unreacted iron oxide in the slag. That's around 6000F. So there are "hot spots" in the reaction.

I have designed a t-mite furnace I call "the star chamber", that utilizes a lot of insulation and a large outside heat source. Heat on more heat. I imagine the "flame" in the middle of the reaction is approaching low fusion temps. I guess around 8 grand F. I'll have to set up a cheap spectro to see one day.

I have found MgO works the best as far as heat resistance, liquid resistance and cleanness. But it's very hard to bind into a usable ceramic form.
I was wondering if anyone had any other suggestions. Thanks for the link.

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I know that there are a lot of complicated thermal dynamics going on.


nominated for an honorary doctorate of understatement :P

this may be of some interest
http://www.pat2pdf.org/patents/pat5152830.pdf (direct download)
thermite process for producing a metal or alloy (92)

a new thermite process with which the heat generated in the thermite reaction can be regulated by appropriately using cooling and exothermic agents at rates that can be controlled at each stage of the metallurgical reaction so that a high quality metal or alloy may be produced at a high yeild


In their first example they are employing quicklime (Calcium Oxide direct download again) as a fluxslag forming material and sodium chlorate as the exothermic agent (oxidizing agent commonly employed in oxygen candles)


Id check all the chemical reactions of course but a layered charging system might be just the ticket ;)

Good luck

ps attempting to order sodium chlorate would likely attract attention ;)
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Id check all the chemical reactions of course but a layered charging system might be just the ticket

Good luck

ps attempting to order sodium chlorate would likely attract attention




Thanks. I ran across that while doing a patent search for my furnace:D

I've fooled around a little with the layered system, but it wasn't too complicated. It's good for adding carbon to make a certain alloy. My furnace is more mechanical, as it utilizes "drop mixing" and the slag is used as a "lid".

Jerry, while reading "Steelmaking Before Bessemer" vol II Crucible Steel, there was a reference to making Magnesia blocks by mixing it with something and heating. I'll try to dig up the exact reference for you this weekend.


That would be awsome. Adell's listed the old timey stuff as "magnesia tar". Have no idea what it was, but it must have been some sort of carbon binder.:confused:
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old timey ehh....


Refractories and Furnaces 1912 PDF or full view google books)

page 93 The manufacture of Grecian Magnesia Bricks

various binders including tar

also page 96 Mortars

doesn't reveal much more
"ordinary mortars used consist of 90 per cent fine magnesia and 10 per cent tar; "

and all full view books in category
subject:"Refractory materials" - Google Book Search

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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.

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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..

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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.

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