Theoretical Heat Treating Question

[Will W.]

Hello all. 

I have had a theoretical metallurgical question rattling around in my head for a few days now. It seems impractical, in truth, and I'm never going to attempt this. Just food for thought. 

Let's say that someone welded up a billet containing W2, O1, and A2, with the goal of making a knife. How would one go about heat treating this knife? Since it contains water hardening, oil hardening, and air hardening steels, I see no effective way to actually do it. Keep in mind I'm not a master bladesmith or an expert metallurgist. It's probably more advisable to just not make a knife from all three but it's a question that I've been pondering for some time, and I want to see what other members think of it. 

 

[Steve Sells]

I will relocate this to the knife making section where this is already discussed, I suggest  you read through that section and you may find your answer

[Will W.]

Apologies. I thought it would fit better in general discussion, but I suppose it is about a knife after all. 

I tried to find info on this subject. I guess I'll have to dig a little deeper. 

[Latticino]

As regards your theoretical question: I would quench in oil.  My logic: I have hardened W2 and O1 in an oil quench before (in separate instances, not together), and wouldn't anticipate that A2 would suffer from a more accelerated quench rate (nor would it be particularly better for the knife edge anyway, so who cares how well it hardens...).  Of course, I can't see a reason to use A2 as part of a knife billet anyway, so it really isn't all that interesting a question.

[Will W.]

Thank you for the response Latticino. 

It seems like an odd combination of steels, I know. The main premise was combining air hardening, oil hardening, and water hardening steels. I also assumed the oil quench would be the best route, as it's sort of the happy medium, if you will. 

[Steve Sells]

O1 can air harden in a knife thickness, therefore since the normal method of deciding how to harden a unknown steel is try air then if it does not harden try oil, starting with oil makes no sense,  oil quenching may shatter A2 which is why its in the air hardening class

this is my last comment on this , I wont say any more since I ALREADY DID AND YOU REFUSED TO READ IT in the pinned HT post

[Will W.]

I hate to seem arguementative Steve, but I refused nothing. I merely said I had to dig a little deeper.

I had already read the pinned topic a while ago, but apparently it slipped my memory that the information was there, or maybe I overlooked it back then. I suppose it would have been wise to re-read that first before digging through the threads. I apologize for my ignorance. 

Regarding the A2, I realize an oil quench may be a little extreme for that alloy, but that's what makes the question so perplexing in my opinion. 

I was unaware that O1 could air harden in a thin cross section. As always, thank you for the knowledge.