Could somebody please tell me how long and at what temperature to anneal a small part made of 8620 that has been case hardened so that it can be welded on. Or does it need to be annealed at all prior to welding. Thanks.

From this info I don't think you'll need to anneal first but preheating is a good idea: 8620

Right. It depends on how deep the case is; usually modern "case hardening" is fairly shallow and is mainly for looks. Your TIG arc will cut right through it and melt it. 8620 has little carbon of it's own, hence the "20" thing.

Thanks for the reply.

If you have to anneal a 'subcritical anneal" is much better as it reduced any warping problem and reduces any oxidation problem too.
1200 F for two hours ,perhaps a bit shorter for small parts.
Any welding with more than .50 carbon is much safer if preheated to at least 400 F.Post heating also is sometimes used .

The case on most of that crap is almost non existent. I get a lot of guys coming in with parts from Italian and Spanish made guns made from that crap that the case has worn through in only a few shots. I have tried polishing sears and hammers with rouge and mirror finish wheels only to break through with light pressure. I don't think I would worry about welding it. Forget trying to harden it after though. Some people think it's great material and gods answer for everything, but to me it's just another kind of cheap, buzzard grade material like 1018. Makes good high pressure pig fences and high performance hand railing.

Someones gonna be mad at me. S I G H !

No one is going to be mad at you. Well, not for this anyway.

quote:

Originally posted by dpcd:
No one is going to be mad at you. Well, not for this anyway.

I got you figured out dpcd. You're just saving it all up for one, big, crushing blow. he he he

Good thing an international border separates us. Wait, those don't work, do they?

quote:

Originally posted by dpcd:
Good thing an international border separates us. Wait, those don't work, do they?

I'm gonna talk to The Don, as soon as he's king and have him build a wall to keep you guys from sneaking up here and swiping our beer and rye. Same as he's doing for Mexico, to keep you guys from littering their beaches and drinking up all the tequila. he he he

8620 - buzzard grade ? I'll have to look that up it's a new term for me. Actually it's got Ni, Cr, Mo in addition to carbon.
Like so much of that stuff - anneal, do all your welding machining etc then re-case harden. Yes a PITA . OR talk him into buying a real gun !!

So can it be recolored or cased after welding without annealing as well.

If you use the proper alloy redoing the CCH will not be a problem. 8620 and 1018 are hardy the same but both do lend themselves to the CCH process well. Correctly hardened 8620 is an excellent steel. It works very well for things like frames and hammers. The thickness of the CCH is determined by the process not the material. What are you working on?

Steve Earl wesson hammer.

I reworked mine as well but did not weld on it.

Let me restate my question. After I finish my welding job, will the hammer need to be annealed prior to undergoing recolor and or hardening for the second time.

Somewhat of a guess as to what you have as far as carbon content , most likely not.

I always pack anneal any CCH part before re-hardening. You reduce the chances of stress issues, warping and over hardening by annealing. This is especially important on thin sections such as the hammer spur.

SKB- Can you explain pack annealing. Is this something I can do at the house or do I need a furnace.

Proper temperature as in a furnace is always better. My suggestion for a "sub-critical anneal" 1200 F is below the typical hardening temp therefore no hardening ,no significant oxidation, and eliminating stresses and warping !!

Parts are placed in a crucible and surrounded with charcoal and then brought up to temperature. When I anneal I set my furnace at 1450 degrees. Some scaling does occur but not much. Best of luck.
Steve

Thanks all for the info.