I've dealt with at least a couple flavors of heat treating outfits: We
used a small tool and die orientated place that would do all of our
special cutters, punch dies, etc. They did all of their work in small
ovens, fully instrumented, dealt with tool alloys all the time. Just
specify the alloy and the Rockwell and you got it back two days later.
It's been a few years but IIRC they had a minimum charge of about $35 to
run one part or small group of parts. More weight meant longer time in
the oven and a few $$ more.

The other shops were high volume production places. We also did one job
that had 16 4130 frames mounted in a rack that went into a 8' diameter
by 16' deep pit furnace. 3 pits in a row, (high temp, quench, temper)
with an overhead crane. $500 for the lot.

These same shops had all sorts of other equipment: conveyor furnaces,
vacumn furnaces, batch furnaces, etc. Pricing is dependent on the
handling required (manual placement vs conveyor), special treatment
(nitrogen atmosphere for nitriding), and length of time in the furnace
(thick part need a longer soak time)

I'm sure that you can get some competitive bids once you get to 100 at a
time. I'd toss out a SWAG number but you really didn't give enough
detail on the part.

Keep in mind that if your "cube" is anyere near solid (eg a block with a
few holes drilled in it), heat treating gets real fussy. It takes a
longer time to get the whole part up to temp, quenching evenly is
difficult. And then there is the warpage and shrinkage problems. If you
just call up a volume place and dont have ready answers about what
tolerances you can live with, they will give you the run around.

The other Thomas Gardner wrote:

Subject pretty much says it all: What can one expect to pay for various
forms of heat treatment (for hardening, not annealing)? I've been under
the assumption that any kind of heat-treat is pretty spendy, so I've
been trying to pick materials that can get by without, but some folks
are telling me it ain't so bad. I can find no pointers on price, though.
Not so bad to one guy could be a back breaker to another...

I know different materials are going to require different procedures,
so I would expect the costs to vary. However, does anyone have have any
rules of thumb to get me in the ballpark of what I might expect for at
least a few of the various procedures? Knowing the price differences
in the treatment types would also help me in material selection.

For a general idea, think a cube of steel about 3.5" on a side. That
should be about the right ballpark. Probably doing these in respectable
quantity, like maybe a few hundred in a squirt. Not vast quantity, but
respectable.

Thanks,
tg.