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A comment on Debris field found in search for missing submersible. Parent comment

Re:Debris field found in search for missing submersible by bumby on Thursday June 22, 2023 @03:19PM (#36437293)
>Carbon fibers is great for lightweight things that need to bend, terrible for things to be relied under pressure.

Composite Overwrapped Pressure Vessels (COPVs) are fairly common in cases where a pressurized system needs to be relatively lightweight (e.g., spacecraft). To your point though, the failure mechanisms can be hard to model.

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Re:Debris field found in search for missing submersible by dmpk2k on Thursday June 22, 2023 @03:50PM (#36437786)
In that case it's taking advantage of carbon fiber's strength under tension.

For a sub you have the opposite problem, which carbon fiber is very weak at.

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Re:Debris field found in search for missing submersible by bumby on Friday June 23, 2023 @11:33AM (#36448297)
Take this with a grain of salt because I worked on the data acquisition side of COPV testing and not the engineering side, but my understanding is that while carbon fiber is strong in tension but weak in compression, epoxy is strong in compression but weak in tension. So the combination is thought to make a vessel strong in both.
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