this post was submitted on 23 Jan 2025
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About an inch deep all along one side of the sheet, it split in half.

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[–] Starb3an 6 points 3 days ago (1 children)

Internal stresses. I believe it's annealing that can remove those stresses. I think the internal stresses are caused by the cold rolling process.

[–] [email protected] 3 points 3 days ago (1 children)

Oh, cool.

So those stresses create an internal plane where it fails?

[–] Starb3an 4 points 2 days ago

From what I've seen yes. I'm by no means an expert. I've seen slices cut from larger blocks that then warp like a banana.

[–] [email protected] 6 points 3 days ago (1 children)

Any metallurgists around here? Be interesting to hear how this happens.

[–] [email protected] 13 points 3 days ago

I'm not a metallurgist, but I am good at educated guesses.

knowing how those sheets are made, they are cast poured into an ingot and then sent thru a series of progressive rollers at a high temp. Basically the cross section of the ingot simply gets smashed and stretched into a sheet of X thickness. I'll bet there was a discontinuity in the ingot pour (possibly a stop-start due to a short run, or machine/human error, accidental splash of water, etc) that resulted in an contaminated layer of the pour. Then when it was rolled out that discontinuity is maintained at the same point in the cross section.

[–] [email protected] 3 points 3 days ago* (last edited 3 days ago) (1 children)

My work produces aluminum in various thicknesses. Can you tell me where you purchased the sheet from? If it was my employer, I'm sure they'd want to hear about it. Feel free to PM me.

[–] [email protected] 8 points 3 days ago

We already reached out to our supplier, and they are replacing the whole pallet. I'll pm u tho