General welding questions that dont fit in TIG, MIG, Stick, or Certification etc.
Jakedaawg
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Well, let's say you have some 5052 ~.060-~.100. Let's say you anneal it so you can form it to the complex curvy shape you want. How then do you get it back to its pre-annealing (if you will) hardness/strength.

I dont really want to put into the airwaves what exactly I am building. Think pontoon type material (.083) 5052 sheet aluminum. Annealed, spun, formed. But I want to get it back to its pre-annealed state after doing the work.
Miller Dynasty 280 DX, Lincoln 210 MP, More tools than I have boxes for and a really messy shop.
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From this site

"Aluminum 5052 also happens to be the strongest non-heat-treatable sheet and plate in common use. 5052 isn’t just easily welded and highly corrosion-resistant, it is also tough and strong. It has good drawing properties and a high rate of work hardening. Its overall versatility, not to mention excellent value, makes it one of the most serviceable alloys available."
Richard
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Jakedaawg
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I guess what that is saying is make my part and use will return it to its normal state.
Miller Dynasty 280 DX, Lincoln 210 MP, More tools than I have boxes for and a really messy shop.
BugHunter
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Jakedaawg wrote:I guess what that is saying is make my part and use will return it to its normal state.
No, it will not. Aluminum isn't like steel in the way it hardens and heat treats. There are similarities, but with aluminum the times for the processes are longer. Sometimes an aging furnace is needed, sometimes you need to stop the hardening process or it'll continue to get brittle, it varies by alloy and I know very little about it. Never had the occasion to heat treat any. Probably for fun I should try.

To do a precipitation hardening on it, it'll take a long time in an oven at a very specific temp. Followed by quench in water or quench in air depending on what temp was used. I don't recall the temps but there's a low temp you could do at home but it takes forever, and the high temp can't be achieved without a heat treat oven.
VA-Sawyer
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5052 can NOT be heat treated. It can be work hardened.
There are 2 major groups of aluminum alloys, those that can be heat treated, and those that cannot.
No sense dying with unused welding rod, so light 'em up!
VA-Sawyer
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Back in the late 70's, while attending Aircraft Mechanic classes at Purdue, we toured the Alcoa factory in Lafayette. I still remember one of the heat treating rooms we walked into. As I recall, it was a bit bigger than a basketball court, with 2 HT units. Each unit had what looked a lot like an above ground steel swimming pool, 30 to 40 ft in diameter.
Above each pool, up close to the ceiling, was a circular inverted trough. A gas line fed flame nozzles around the lower inside edge of the trough.
The parts were lifted up into the trough with chains, and held there during the 'heat soaking' part of the cycle. The flames were below the parts, and the inverted trough acted as an oven. Once the parts met the time/temp requirements, the chains were released, and the parts did a free fall into the coolant below. As I recall, the coolant was a brine solution, and not the pure water that I was expecting. I do remember the time from being oven hot, to room temp was critical. A very impressive thing to see in action.
No sense dying with unused welding rod, so light 'em up!
Jakedaawg
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Well, maybe I just need to figure out how to bend it without annealing it.
Miller Dynasty 280 DX, Lincoln 210 MP, More tools than I have boxes for and a really messy shop.
cj737
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Jakedaawg wrote:Well, maybe I just need to figure out how to bend it without annealing it.
You can heat it to soften it to bend. It will recover to its prior hardened state after quenching. It does not need (nor can it be) heat treated afterwards.
kiwi2wheels
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And depending on the amount of forming the material is going through, you may have to anneal it more than once.
BugHunter
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I would do a small test piece before I tried doing all this forming on the actual parts and expecting it to ever be hard again. I would be very surprised if you can get it back to even 60% of it's original hardness without a controlled temp furnace. Ductility is almost certainly going to be an issue and I'd expect if you do any tight bends there'll be stress risers on the outside of the turns where it'll later break if subjected to ANY fatigue.
cj737
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BugHunter wrote:I would do a small test piece before I tried doing all this forming on the actual parts and expecting it to ever be hard again. I would be very surprised if you can get it back to even 60% of it's original hardness without a controlled temp furnace. Ductility is almost certainly going to be an issue and I'd expect if you do any tight bends there'll be stress risers on the outside of the turns where it'll later break if subjected to ANY fatigue.
Do you even pay attention? It’s 5052. It is not heat treatable for hardening. :x :roll:
BugHunter
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cj737 wrote:
BugHunter wrote:I would do a small test piece before I tried doing all this forming on the actual parts and expecting it to ever be hard again. I would be very surprised if you can get it back to even 60% of it's original hardness without a controlled temp furnace. Ductility is almost certainly going to be an issue and I'd expect if you do any tight bends there'll be stress risers on the outside of the turns where it'll later break if subjected to ANY fatigue.
Do you even pay attention? It’s 5052. It is not heat treatable for hardening. :x :roll:
Do you know anything at all about aluminum?
If it's not "Heat Treatable", why do you say quenching will restore it to it's original state?

You made this statement:
You can heat it to soften it to bend. It will recover to its prior hardened state after quenching.
No...it...will...not...

Go grab a hunk of 5000 series and anneal it, then let me know how that "recovery" works out. You'll be quenching a while.

I don't know why you've got such a burr under your saddle for everything I say lately, but holy cow man, give it a rest. Take any one of the statements I made in that post and let me know which one was incorrect?
VA-Sawyer
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If you heat 5052, but keep it well below the annealing temperature of 650F, it will be softer while hot, then revert to its prior condition when cooled. The rate of cooling is immaterial when hot working, or annealing.
If you buy Annealed sheet and form it, it will work harden. If needed, you can re-anneal multiple times to prevent 'frosting'. ( White areas of micro-cracking due to excessive working).
Last edited by VA-Sawyer on Thu Dec 24, 2020 2:09 am, edited 1 time in total.
No sense dying with unused welding rod, so light 'em up!
cj737
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VA-Sawyer wrote:If you heat 5052, but keep it well below the annealing temperature of 650F, it will be softer while hot, then revert to its prior condition when cooled. The rate of cooling is immaterial when hot working, or annealing.
If you buy Annealed sheet and form it, it will work harden. If needed, you can re-anneal multiple to times to prevent 'frosting'. ( White areas of micro-cracking due to excessive working).
Thank you for explaining it to BH.
VA-Sawyer
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Be nice. :) I think BH just got a wire crossed on this one. I've done it myself multiple times. Normally I find BH to be on the ball with his posts, and an asset to this forum. Maybe he is having an off day or two. Let's just focus on trying to help the OP, and try to make a few allowances.
Reliable info for 5052 is available with just a few minutes on google.

Each alloy of aluminum is kinda in its own world when it comes to welding, forming, heat treating, etc. If you have a sheet of unmarked aluminum, it is almost worthless in the aviation world. Other than being lighter than steel, almost any other statement made for 1 alloy would be dead wrong for some other alloy of aluminum.
No sense dying with unused welding rod, so light 'em up!
BugHunter
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The last week has been about as bad as it can get, but that has nothing to do with this. :lol:

I just got in 16K# of 5154 yesterday and that's almost exactly the same chemistry as 5052. A touch more chromium and manganese but all but identical. Actually, within the tolerance of the chemistry, you could actually designate the exact same metal as either alloy 5154 or 5052 (using the limits of the tolerances on content). If I get time I'll throw some in the furnace today and try it at different temps. I'm still skeptical about using a torch and just heating it. Knowing what 500 is vs 600 without some method of measure, I'll say best of luck. And in my experience, there's not a lot of difference between 400 and room temp. Go any too hot and it's a wet noodle.

But especially at the thicknesses the OP said he's working with, I'm not sure how he's going to heat any amount of this and keep it from annealing. So I'll again say, try a small piece. He's talking about 16ga and 11ga sheet. I really wish him luck on the 16ga keeping the heat from going too high.
BugHunter
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You could try this. They also make a thinner for it.

https://www.ebay.com/itm/Tempilaq-heat- ... SwIOtbaziS


Also in pen form, but I'm not sure these are real-time indicators (meaning, can heat, reheat, and show color repeatedly).

https://www.amazon.com/Tempil°-TS0650-T ... B0013L76I4
Last edited by BugHunter on Thu Dec 24, 2020 11:30 am, edited 1 time in total.
Jakedaawg
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Thanks guys. I appreciate the knowledge. I now have some idea of what information and practices I am looking to learn.
Miller Dynasty 280 DX, Lincoln 210 MP, More tools than I have boxes for and a really messy shop.
Jakedaawg
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I am also thinking that it may not really matter in my case. Pontoon companies use this stuff all the time. They bend it, weld it, spin it for end caps, etc. They do things as cheap as possible. I guarantee they dont have any heat treating going on. Perhaps they do this without annealing. Maybe I just need bigger press and lathe and rollers. Bummer, I hate buying tools. Not;)

What i am doing gets its strength from its shape more than from the material.

Anyways, thanks again.
Miller Dynasty 280 DX, Lincoln 210 MP, More tools than I have boxes for and a really messy shop.
BugHunter
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I cold work 5154, 6201 and 6063 all the time. Boatloads of it. I also purchase it after a custom production process with the 5154 at H19 and 53KSI, but the 6201 over aged to reduce back to 38.5-43KSI. (Tensile). The 5154 is easily twice as ductile at 53K as the 6201 is at 40. Elongation is greater, tensile higher, ductility higher. Rebound on the 5154 appears about equal in spite of being ~12KSI greater tensile as I receive it.

So I stuck 16 pcs in the oven, and this is some serious back-of-the-napkin engineering/testing here, but... Doing my working IN the oven, so as not to lose any temperature, the primary thing I notice is a reduction in rebound. Now, there's "Some" reduction in effort to work the stuff, but that is so slight it's almost lost in the noise at least with the 16ga stuff I'm using. At 350F I'd say the increase in malleability is <5%. I'm going from how much rebound difference I see in two parts, one from the oven and one at room temp.

Jump up to 490F (just happens to be where it came up to when I had time to get to it), now there's a difference in feel when working it, definitely less effort but not like a 50% reduction in effort. 30%???? Eh, maybe. So it is easier, but you'll have a hard time keeping that temp while you get it in a brake to work it. "Impossible" comes to mind...

Afterward, does it return to it's preheated state??? "Mostly". From 350 I'd say it does. But at 350 you don't gain much at the working process, IMHO . Near 500 where you have those gains, I'd say you're where there's a permanent loss of strength after cooling. 10%??? Yea... I'd say at least. Going up above that I bet finished strength is going to drop off like a rock, so I'd use 500 as the upper limit if you really are trying to heat it to the upper limit and hope it doesn't cool much before you get it in a brake or whatever to move it around.

I didn't try a sharp bend. I can do those on 5154 or 6201 16ga cold, so long as I'm not working it multiple times. One shot and done, fine. 6000 series will occasionally break or stress crack if there's an impurity right in the bend, but for general purposes, it survives a single 70-90 deg bend at 1/16" radius.

Everything I did on the oven parts was no less than 1" radius. I was looking for how it would react and return to shape and rebound, which tells me how many times you'd have to clobber it to a shape to make it stay there. Less is obviously better. Once is best.

If I were going to do brake work on it, I'd consider anti-friction tape, something that will keep from adding stretching stress on the part as it moves. The less directions you pull on it, the less likely you are to have stress risers (stress cracks on the outside edges of your radius). Lube might help too. Ideally, 0 friction will be beneficial.
VA-Sawyer wrote:Be nice. :) I think BH just got a wire crossed on this one. I've done it myself multiple times. Normally I find BH to be on the ball with his posts, and an asset to this forum.
Arguably, the first 3/5ths of an asset, maybe. :lol:
BugHunter
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As a side note, my certs say 53988 psi (53.988ksi) and 3.6% elongation. That 3.6% used along with the thickness of your part you wish to bend will tell you how far you can safely go (cold) and not have structure issues. Now, I'm sure there's more to the calculation than just inside diameter : outside diameter =3.6% = min radius. But for this purpose it should be pretty close to that.
Jakedaawg
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Thanks for your experience and observations.

The prototypes i have made were done by heating with a weed burner type rig. I then let it cool. Spun it over my die I guess you would call that, then welded in my bent parts over a void thats cut out with a pattern.

I dont know how hot I got them. Hot enough to be easier to work after cooling so that must have been over the annealing temp.

I was just going for proof of concept. All were installed on rental boats and subject to a season of abuse with no failures.

Now I am going to try to sell the idea but we are trying to get our ducks in a row and figure out how to make sure we dont loose out when we try and find someone to make them.
Miller Dynasty 280 DX, Lincoln 210 MP, More tools than I have boxes for and a really messy shop.
BugHunter
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That's exactly my fear of doing it with a flame is not having control over the temps. If you'd like to try what I did, I never went above temps you can achieve in your home gas/electric oven. I think that's a formality though since I just gave you my findings, but if you wanted to try it with something like a Nesco roaster oven like you bake turkeys or hams in, that would work and you could pull a part and stuff it in the brake in 10 sec, and see what gains you can have on a sharp bend. Assuming you even need a sharp bend.

Yes, if it went soft after cooling, you were above the annealing temp. I was fast approaching it here. Temps are really non-negotiable with a lot of materials. For instance, on my 6201, the difference between 53KSI and a nominal 41KSI is 4 min 30 sec extra in the aging furnace. That's it. I don't get to observe the process of making my 5154 because it's halfway across the country. But I regularly get to see the 6201 process, and I've gotta tell you, if that doesn't make you leery about trying to alter the properties at home, nothing will. :D
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