"rashid111" wrote in message
oups.com...

And about argon: for now I use tool wrap steel and it works OK, but
I do get some scaling and softer decarb in the outer layer - which I
grind off. Even using the paper-in-the-foil-bag trick. Assuming I have
a top-load oven and it's rather air tight below the lid, can I simply
flood the interior with 2-3 CF of argon before starting the heat treat
cycle ? Being heavier than air , will it stay "put" inside of the oven
- even when heated up to 1800F-2000F ?

I know some people keep moving inert gas through the oven throughout
the cycle (at slower rate), might need to do the same. Drill a smallish
hole through firebrick, stick some time of copper tubing with connector
to attach the argon hose to - am I correct in my thinking ?


What are typical prices for smaller argon bottles (need pure argon I
reckon, not the CO2 or Oxy mixes) ? Will also need a flow meter .
Also am I correct in assuming that argon is 100% to use ?



I think you need to make a retort. This is a container that is sealed shut
except for your gas input and output. This might be more complex than a
home shop justifies.

A friend of mine worked at a place that used hydrogen as their gas, and they
burned off the exhaust. They did mostly furnace brazing there. They had
two types of retorts. one was a metal can about the size of a common trash
can. It had a flange formed on one end and the other end had a pipe flange
welded on. A flat lid with another pipe flange was then welded to the
flange to seal the retort and then an electric furnace was lowered on the
base.

These had to be ground open after each heat and were tossed after about 10
heats.

The other style had the can inverted and was sealed against a water cooled
gasket.

I don't think hydrogen would be good for all material as in some cases it
may cause imbrittlement.

--

Roger Shoaf

About the time I had mastered getting the toothpaste back in the tube, then
they come up with this striped stuff.