M2 tool steel, can i heat treat in gas forge

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First of all let me explain myself. Usually I stick to easily heat treated steels but... I was talking to a friend of my dad's and he told me he had some really good knife steel at his house. I told him I would look at it just to be courteous. So he brings me about 2 foot of M2 stamped steel. It is stamped hardened and ready for use. its 1/8x2x2foot? Im wondering if it would be possible to anneal it, work it, then heat treat it in my gas forge. I read the stats on crucible and don't know if i can pull it off... Especially the 1000 degree temper. Also, Would it be worth sending out 2 knives for heat treat if i could find someone to do it?

M2
1500/1550-preheat
2050/2200-austentize
3-10-soak
AIR (5)-recommended quench medium
1000/1100-temper
58/65-typical hardness
 
The hardened bar stock is used to make industrial cutting tools, not knives. You can't anneal or re-HT it without a HT oven. You could grind it as-is, but that really requires a water cooled grinder and equipment. It would be a real bear to hand sand.

I would not make a knife out of the steel he provided. To have it annealed professionally, then hardened again after making a knife would not be sensible, cost wise.
Also, while M2 certainly can make a knife, it has no real benefit over the many good blade steel choices. It's primary purpose is to have a very tough wear resistant edge in production and workshop cutting tools. The things most regular use knives do, do not require this. Also, the large amount of carbides from the high tungsten, chromium, and molybdenum, will make getting a fine slicing edge unlikely.

http://www.zknives.com/knives/steels/steelgraph.php?nm=m2
 
Stacy E. Apelt - Bladesmith said:
The hardened bar stock is used to make industrial cutting tools, not knives. You can't anneal or re-HT it without a HT oven. You could grind it as-is, but that really requires a water cooled grinder and equipment. It would be a real bear to hand sand.

I would not make a knife out of the steel he provided. To have it annealed professionally, then hardened again after making a knife would not be sensible, cost wise.
Also, while M2 certainly can make a knife, it has no real benefit over the many good blade steel choices. It's primary purpose is to have a very tough wear resistant edge in production and workshop cutting tools. The things most regular use knives do, do not require this. Also, the large amount of carbides from the high tungsten, chromium, and molybdenum, will make getting a fine slicing edge unlikely.

http://www.zknives.com/knives/steels/steelgraph.php?nm=m2
Click to expand...

Thank you for chiming in. He called me this morning and said he found some other steel. It's 1/8x3x18in and its stamped sae O1. And in marker next to it it says oil quench only with a bunch of exclamation points. I'm really pumped about the O1, it's what I try to use if I use a known steel. All of this steel came from an old machine shop that him and my dad picked through when it closed. I have roughly 100 new files from there. He also has some large buzz saw blades that came from the same shop. I have no idea why they were there.
 
Heat treating M2 isn't something that you can do in a forge. The temperatures aren't typically high enough for long enough. I've made some knives out of the M2 saw blades I was given. I ground them (2) using a belt sander, and sharpened them on the same sander with a leather belt. I later resharpened on stones and tested them, and to this day it was some of the longest edge holding steel at high sharpness I've tried. It worked very well, but the blades were only 1mm thick, requiring minimal metal removal. I currently have a kurimuki in M2 that I've not done a handle for yet.

Stacy, I'm curious what you'd think of M4, as it's another high speed steel that is fairly common in knives. It has even more carbides than M2. It's advantage is being more available in annealed form to knife makers.
 
I didn't mention it, but I have used M2 for knives. It was fine, but the edge was best suited for a higher angle rough use knife. I have used M2 machine hacksaw blades, and M2 bar stock.

I have made quite a few knives in CPM-M4. I tested it for crucible when they were getting ready to market it. It makes a great long wearing edge knife. I would call it great for a camp knife. I found it able to take a good edge, but not a fine slicer edge. I made an M4 cleaver that probably still is sharp today :) . An M4 large fillet knife for big fish was not a really smooth slicer, no matter how much I worked the edge on belts, diamond plates, or stones. M4 chefs blades were pretty much a failure in use, as it just didn't perform as well as much cheaper and simpler steels.

Looked at under high magnification, the edge on M4 looks like a band saw blade compared to CPM-S35VN. That sounds worse than it is. AEB-L looks pretty smooth, but most all high alloy steels with carbide formers have a serrated looking edge under magnification. The bigger and harder the carbides, the more severe the serration effect. As a contrast, under magnification ( and in used) Hitachi White paper shows why it will slice like almost no other steel.

M2, M3, and M4 make up a class of high molybdenum ( Thus the M) high speed tool steels. With the high molybdenum, vanadium, chromium, and tungsten, these tool steels excel in wear resistance. They also hold their hardness and strength up to higher temperatures than most steels, which isn't a knife related attribute. Toughness is what the M series steels are breed for. On some knives, that is a big asset worth the main spotlight. On others it isn't worth much consideration at all.

AEB-L is the other end of the spectrum, with lots of chromium, but no excess carbon to bond with it. It forms virtually no carbides. It is as keen edged as 1080/1084, but as stainless as 440C. I usually describe it as stainless 1080.
 
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Now O1 even I can Heat treat in a forge. Good luck with that. O1 is popular for a lot of reasons. Performance is one of them.

Just to be picky, Stacy, I think you meant the M is for Molybdenum in the M series steels. Manganese helps, but it won't replace moly. I suspect you have different standards for a low angle slicing blade than I do. I had no trouble getting a very sharp and fine slicing edge on my M2 blades. I'll email you about it.
 
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