Engineers develop bone-like metal foam that can be 'healed' at room temperature | Hacker News Reader

Engineers develop bone-like metal foam that can be 'healed' at room temperature

phys.org

64 pointsrespinal16 comments

The only interesting part seems to be that it resembles bone and "repair" can be called "healing" instead.

>While this room-temperature approach is not truly "self-healing" because it requires an external power source and raw materials, Pikul sees it being in line with how self-healing occurs in the body.

The interesting part is that the process is not fusing the structure and keeps it, mostly intact.

Normal electroplating would fuse the surfaces with a layer of metal, rather than keeping the foam structure.

The problem here would be repairing big breaks though. Plus maybe working with metals that do not readily work in electroplating bath, like aluminium.

Bone requires an external power source too.

And raw materials.

them bones them bones need calcium!

This is a fascinating technique and an interesting step forward.

I noticed:

> The new nickel, however, reduces the healing efficiency when repeatedly using this technique. Because the healed areas no longer have a polymer coating, nickel would continue to amass there should another piece of the sample need to be healed.

Yes, so I reckoned this won't be useful for "growing" foam or big breaks. At that point you'd fashion a right shape chunk of foam and fuse it on both sides I suppose.

Dip it into coating again after "healing"

This is interesting, I'm curious what applications this would be useful for. They hint at some potential uses toward the end, but don't elaborate much.

Presumably it'd be useful in applications where the parts would normally fail regularly.

You can dip your giant robots into an electrolysis bath after taking on invaders from another dimension a la neon genesis evangelion.

I'd also assume it'd be useful for repair of critical components that undergo trauma. Such as bridges, and buildings that might be struck by vehicles, or repairing prosthetics and other things that can be damaged at the same time as the human they're attached to.

You'd need to make your bridges out of this fancy metal foam instead of boring old (read: "cheap") hot rolled I beams. That would be a massive technical challenge. It's theoretically possible but would require new construction techniques. At the very least we'd need to figure out a new way to protect it from the elements that doesn't negate the self healing properties (this foam doesn't look closed cell, hello corrosion) Probably expensive beyond all practicality.

Furthermore, vehicles basically just bounce off the structural elements of bridges and other structures like that. It's not really a problem.

If anything we'll see this kind of stuff used in expensive niche applications. Low volume bespoke electronics in high vibration environments would benefit from being able to "heal" like this. I can also see it being useful when applied as a coating that protects the material underneath, basically a self touching up paint job (like galvanizing, but possibly with a wider array of materials than just zinc). This could be very useful for items in corrosive environments.

This is mostly useful to repair expensive and customized things like prosthetics. The other examples would just get the parts replaced as they're not customized.

How does it not short out when the foam isn't completely severed? It seems like the electroplating current would just short circuit through the non-broken connections.

Can we please stop with the clickbait scientific discoveries? They all follow the same formula of: 'x develops y which can "z"'. Where "z", which is always in quotes, is a gross sensationalization of some discovery or effect.

Thank you, yes.

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