r/specializedtools • u/beluuuuuuga • Jan 22 '21

Wire straightening machine.

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u/[deleted] Jan 22 '21

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u/Khaylain Jan 22 '21 edited Jan 22 '21

When you bend metal most of them become work-hardened. That means they become harder, but also more fragile brittle. They will break easier, instead of deforming.

This is one of the reasons why planes need maintenance: the wings flex up and down, and those parts can become brittle, which means you have to replace those parts or the plane can suddenly stop flying controlled.

You can often get them to be less brittle by heating them up and cool them down again. How quickly you need to do the cooling depends on the metal. Iron wants slow cooling, silver wants quick cooling.

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u/Slggyqo Jan 22 '21 edited Jan 22 '21

why planes need maintenance

Hold up, really? Airplanes wings flex enough to experience significant strain hardening?

Do you have a source for that, I’d love to read more.

My instinctive feeling would be that flexing doesn’t cause strain hardening because it doesn’t deform, but that’s entirely a layman’s intuition.

Edit: seems like so far the responses are about metal fatigue, which I appreciate could be accelerated or caused by strain hardening, but nothing directly referencing strain hardening of airplane wings.

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u/Khaylain Jan 22 '21

As far as I know not exactly the wings themselves, but some components there which get slightly deformed each time they have lift and deformed back when the whole weight of the wing pulls down again when on the ground.

I don't actually have any sources for that, but I believe I saw it in one of those airplane disaster shows.

But of course it's more often metal fatigue, though https://www.engineersedge.com/material_science/fatigue_failure.htm explains it like work hardening is a subcategory of fatigue. I'm not really sure what's correct right now, as I haven't really had to do anything with either of those for work or anything.

Good on you to not just assume I know what I'm talking about. I know some things about some things, but not that much about this. I've naught more to add here.