Inert Gas in HT oven?

[J.D.]

Is it possable to use a flow meter on a bottle of argon gas, and put a flow of the argon in the heat treat oven to eliminate decarb? Thanks in advance for all input.

 

[Nathan the Machinist]

Yes, that's the way I do it. However, my furnace (a little Lindberg Blue) is designed for this. The door is a wedge that fits into the heat chamber and there is a vent on the top, I guess to allow the lighter gasses to vent. If the furnace isn't designed for this I'm not sure how well gas will work. Keep us informed?

BTW, I use foil for blades because they wrap so well, but that's just me.

 

[David Loukides]

Hi JD,
There are ovens that have a inner chamber made out of high temp stainless that you can flood with nitrogen. Try googling Heat treating Muffled ovens. With out the muffle the nitrogen will not force the air out. We had this problem at work and found out that foil wrap worked just as good and better than a leaking muffle. When the part comes out of a muffled oven you will get a little decarb as it cools down but not a lot. It might be a fun project to try, but use scrap steel not a blade to get your flow set up right. I have burned up Plenty of steel at work.
Have Fun!!!!

 

[J.D.]

Thanks for the thoughts on this. This was just a thought I had while setting around here with the flu, to much time to think. I may give it a try sometime, just for the fun of it, would have to get a bottle of argon or nitrogen, I have a flow meter. I use foil on my stainless, but use nothing on carbon steel. Thanks again.

 

[Dan Seaver]

Your not limited to just argon and nitrogen, any element in group 18 of the periodic table should work. Helium is ligher than air so you would need to have the vent hole on the bottom if you used it.

-Dan

 

[A C Richards]

If your elements are enclosed then you can use it directly into the kiln. If not then you need a retort or inner chamber with the gas purging the container. Carbon steel can be coated with an anti scale compound as can the SS but the foil works great for SS.

 

[rashid11]

Just don't go there . Stainless foil is all you need. It works 100% and gives you a much needed piece of mind guarantee. Don't want to spend days grinding a masterpiece to have it decarbed in a botched HT.