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Comment by londons_explore | Hacker News Reader

267Gpa isn't unreasonable to achieve 'in the home'.

For example, if you had a rod of the superconducting material 1mm in diameter, and you wrapped it tightly with a strand of Kevlar (tensile strength 3.6GPa) until it became 100mm diameter, then the center would have a suitable pressure...

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This doesn't seem right, how does a rod go from 1mm in diameter to 100mm in diameter under pressure? Also, how does one "wrap tightly"? The material would fracture under the stress of the first wrap.

You're right - I assume that kevlars spring constant is << the rod's.

If that's the case, you just set the tension in the thread so the Kevlar is near its breaking point, and start winding, like winding thread onto a bobbin...

Not being a mechanical engineer, I don't have an intutive feel for how the additive nature of the pressure develops as you describe. I would have thought that the outer layers would start to compress the inner layers, relaxing some of their stress. Is the a mech-e 101 type of link you could pass along to help get me up to speed? Or maybe you are saying that 3.6 GPa times the ratio of 100 mm to 1 mm gets us to the 360 GPa mark? So you don't need to have layers of Kevlar as your "anvil", you could use something else more rigid, and just wrap one layer of Kevlar around it and develop the needed pressure. Thanks.

Tensile strength is pulling. The diamond anvil needs compressive strength.

A cigarette lighter has compressed gas inside... Yet the walls need tensile strength...

This is true, however in this case the tensile strength of the casing needs to be focused into a small area and that is done by translating the pressure from a large area into a small one.

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