Self-Healing of Fractured Diamond

Does this have any relation to cold welding?

*nanotwinned diamond composite, which is presumably not naturally occurring.

Interested to know what kind of sizes its typically available in.

It's not made in commercial quantities anywhere, so there is no typical availability.

In the paper, they were looking at scales of 1nm, using a high-resolution electron microscope.

The test sample was made via high-pressure/high-temperature compression of "onion carbon" -- itself a very unusual material.

It's an interesting paper, but I don't know if the material's manufacturing method scales -- and, in any case, the self-healing effect is on the smallest possible scale, so it stands to reason that bulk samples, visible to the naked eye, will not exhibit it to any appreciable degree.

> it stands to reason that bulk samples, visible to the naked eye, will not exhibit it to any appreciable degree.

I don't follow. It only takes a single crack to split a sample into two macroscopic pieces. If a small crack begins forming, and likely to either heal or get worse, that seems to have obvious macroscopic effects.

And I thought this was about mental health!