Forging and oil quenching ATS-34???

Chiro75

Chiro75

Joined
Feb 4, 1999
Messages
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On another forum this guy was giving advice to a guy who is making his first few knives my old way: files, stones, sandpaper, etc. He mentions in his post that he forged part of his first knife, which he made from ATS-34, and used oil to quench it. Are either of these things effective and do they actually accomplish anything? I've never heard of forged ATS-34, and I know for a fact that you can't oil quench ATS-34 and chuck it in the oven like 10xx, so what would that actually do to a knife, if anything?
 
Obviously since it has been hot rolled to form it can be 'forged'. However one of the things you will find out about forging the more complex steels is that they strongly resist the hammer !!! A machine would make it much easier .Remember also that the heat treatment of something like ATS-34 is very critical as far as temperatures and times , certainly if you want to get the best performance out of it.
 
So, just to clarify, heating ATS-34 to non-magnetic and dumping it in oil probably does what? Will it harden? Obviously you need to use a real heat treat oven for these types of steels, but just for curiosity's sake, what actually would this achieve?
 
Less than optimal would be accomplished.

You would do the actual heat treatment as a seperate process after forging. Yes, you can oil quench ATS-34. For the HT though you probably would opt for plate or rapid air quench since atmosphere control of the steel is very desirable (foil wrap).

RL
 
So, in summary, a backyard caveman knifemaker (hey, that describes me!) probably wouldn't be able to do well HT'ing ATS-34 himself with a propane torch and some veggie oil. Got it! It's interesting what's out there. On this same other forum a guy was showing off a production fixed blade of S30V (or maybe ATS-34) and he had totally reprofiled it, ground in all these deep serrations, etc. Anyway, there was heat discoloration all over the place, rainbowing, etc and I mentioned that he probably ruined his temper by not keeping the temperature of his grinding controlled, then another knifemaker sort of argued with me, saying "I grind on HT'd steel all the time. If it doesn't get to 1000°, don't worry about it..." When I see color changes in steel I assume that means the temper has left the building, but maybe I'm wrong!

Thanks for the input. FWIW, when/if I ever get around to grinding stainless I'll send it out (or I'll have purchased a HT oven, at least!).
 
Some high alloy steels are tempered at really high temps, well above "blue". If it was a carbon steel blade it'd definately be messed up from that, but s30v would probably be ok, I'm not real familier with the temps associated with it.

By the way, if you felt like forging and caveman HTing stainless, I've heard (no personal experience so take your grains of salt) that 440C responds best.
 
the cpm3v im working on right now was tempered at 1000 but it is some wild stuff s30 v on the other hand is said to be best not over 700
all this is right off crucible data sheets btw
 
I have forged kitchen knives out of ATS-34.

It had nothing to do with me thinking it would improve it, and everything to do with the fact that I needed wider stock than what I had on hand.

It is difficult to forge. You have a very narrow window of opportunity to work the steel.

After forging, I ground the scale off and heat-treated in a digital oven.

The guys heat-treating 440C, ATS-34, and the like with propane and mapp gas torches are getting less than optimal results. You NEED a controlled heat source for hitting the proper temps and soak time.

:D
-Nick-

http://www.wheelerknives.com
 
When I see color changes in steel I assume that means the temper has left the building, but maybe I'm wrong!
Click to expand...

From what I understand the 'colors' are caused by a very thin oxidation layer on the surface of the steel, with the different colors corresponding to the temperature change occurring in the metal.

And like you, I was under the impression that if you're seeing the colors form, then you're #$%^ing with the characteristics of the metal.

This page for S30V seems to bear that out, as the 'as quenched' hardness is 60.5, and the tempering temps are between 400 and 1000 degrees, giving differing results for temperature/quenchant used.
PDF format:
http://www.google.com/url?sa=U&star.../dynamicPull.cfm?gradeName=CPM%20S30V&e=10053
HTML format:
http://66.102.7.104/search?q=cache:...eName=CPM%20S30V+tempering+s30v&hl=en&start=1

So, IMHO ...yes, the blade you cited as an 'example' is #$%^ed up compared to it's 'factory' temper ...but maybe still sufficiently hard for use as a cutting implement.
 
most of those steels are air hardening steels...........................

you quench them in the atmosphere, not in oil!!! :p :eek: :p
 
Just for fun awhile back I played around with a mis ground ATS-34 blade and torched heat treat and oil quench. I heated to non-magnetic and held it there for a couple minits and quenched in heated oil. The resulting blade cut very well, within 10% of a cryoed and digital oven heat treated blade. It also was very soft and on harder testing the edge rolled and when put in a vise it bent with little trouble. Never did figure out what was going on. I'm a firm believier that with stainless you need a controlled heat source, forge or oven as long as you can dial it in right, and cryo.
 
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