Annealing stainless

My search and google-fu have failed me.

I need to smash some stainless nuts. Does stainless need to be annealed? Will that change any of the properties as far as being stainless? This will be in a marine environment, submerged with the tides. Mixing in mud and sand to make things as corrosive as possible.

Inquiring minds that want to know.



Owl

I use stainless nuts on stainless cable for my trap extensions. I have never had a problem. No need to anneal.

I assume you want to have the nuts more malleable for your smashing process.
Assumption: The nuts are most likely 300 series stainless and more likely 304.
Most annealing of stainless I've been involved with was under very controlled conditions and under controlled conditions you can achieve better and enhanced corrosion resistance. Typically, Hydrogen and Nitrogen are flooded into the chamber to reduce oxidation of the chromium (Cr) found in stainless and often still requires pickling in nitric or hydrofluoric acid to remove scale.
Your challenge will come from trying to achieve the right temperature (probably 1,100 degrees) with the precise quench time following your hot nuts- my fear would be that you have carbon leaching and trap carbon atoms in the process and further reduce your corrosion resistance, if not timed precisely.
You could try it- hit or miss and maybe passivate with citric acid or orange peels after. I would be inclined to smash a brass nut on the stainless bolt for your application- true that dissimilar metals will corrode faster but you could induce more galvanic reaction by exposing the carbon in annealing on a comparative scale to the corrosive resistance benefits of brass. If to want to get fancy you could add a sacrificial anode like a piece of zinc to your assembly- that will come under attack before the stainless.

That's what I was thinking!

What eagle eye means to say is

Tis too complicated to bother with.

Like EagleEye said, nuts are most likely 304.

It can be annealed but it also work hardens. As soon as you hit it with the hammer, it will be hard again.

That said, I've crushed 304 stainless nuts before. A few will crack, probably from the work hardening, but most worked fine. By crushing them, I'm making them brittle but they were still strong enough to work. I wouldn't trust them if I was building some sort of cable system I needed to save my life but on snares it should be fine.

If you're having problems, you might have nuts made of some other type of SS. 304 is the most common but nuts are available in other types of stainless. Try ordering 303 nuts. 303 isn't as hard and doesn't work harden as readily as 304. No idea how much 303 nuts would cost though.

Yes, stainless will work harden, but as far as crushing nuts, the more times you hit it, the worse it is. Use a big hammer, and get the job done with few hits! If you aneal, keep the temp down, as the alloys will migratewhen heated above the critical temp. To. keep that from happening, the stainless needs a protector from the atmosphere! As in when welding, it uses a shielding gas to accomplish this. The result of heating above the critical range without protection, is what is known as sugaring in the welding trade. Hope that helps you understand this a bit more. You would about need an oven to do the anealing, so Just use a bigger hammer! Good luck.

Why didn't I just say that!

Austenitic stainless steels, which includes all in the 300 series, are not particularly good in a salt water environment. They are susceptible to chloride induced stress corrosion cracking. In your application smashing them will mean they are highly stressed and the salt water will do the rest.

Holy Moses. I see I tapped an inner geek or two. There’s a lot of cool and interesting information here. It’s more than the standard toss them in the wood stove like normal. Thank you.



Owl

A couple good explanations about stainless and it's abilities to be hardened. Wont add any it would be redundant !

Can it be done yes, do you really need such cost and time expenditure for your needs I doubt it !

Most trappers would never have the education, time or equipment to do this nor really the need to. It's expensive to do so
and do it correctly. Just is not worth the investment in my eyes when other applications would suffice just as well.

OK here is the German enginerding perspective. To do the job to suffice for the intended purpose, you need a bigger hammer to get the job done in as few whacks as possible. Forget about all the rest, have a drink and sleep easy before setting them wires.

Yes I too have learned a lot about nuts on this site

It’s all about geeks. It’s what people do. Heck, I geek out about power saws and electricity, that’s what I do everyday for a living. I’ll grab a big hammer and get after it. I do actually appreciate the more intense information, it caused me to look up a few things and learned some stuff along the way. Pretty cool.



Owl

I've had the pleasure of working with some of the most well-schooled and smartest engineers over my career- I would take a farmer over the majority of them on any given day. A lot of times you don't need theory- you need a solution!