A new super-material?

[nickel-city-fab]

Just food for thought, found it courtesy of slashdot. Claim is that there is no practical way to cut this stuff. Basically an aluminum foam with ceramic micro-spheres embedded in it. Article link: https://www.newscientist.com/article...ate-bike-lock/

[MattiJ]

Sounds like easy target for bolt cutters.

[nickel-city-fab]

Sounds like easy target for bolt cutters.

Or plasma.

[Doozer]

If a concrete saw can rip through a slab or a curb section
I doubt this stuff is the problem it claims to be.

-D

[lynnl]

Interesting that all the hype and hoopla about it seemed to be fixated on making more secure bicycle locks.

[chipmaker4130]

And, they didn't say anything about cutting with diamond tools either.

[nickel-city-fab]

I'm wondering about aerospace applications --- acts like AR400 "work hardening" but without the weight

[Paul Alciatore]

...in an "aluminum foam"

So just what acid will dissolve aluminum?

[challenger]

One look from my wife and that stuff is done 😁

[ed_h]

...in an "aluminum foam"

So just what acid will dissolve aluminum?

Hydrofluoric, but strong alkali is more effective than acids, Lye will attack aluminum. If it is hot, the reaction can be pretty violent.

Ed

[macona]

Yup, alumina ceramic balls in aluminum. Diamond will make short work of that. And like Ed says, Lye will dissolve aluminum.

[MattiJ]

Yup, alumina ceramic balls in aluminum. Diamond will make short work of that. And like Ed says, Lye will dissolve aluminum.

Aluminium is pretty effective in loading up abrasive tools.
"original" article in Nature is lot better and doesn't mention stupid bike locks. But I'm not sure if I buy their complex "vibration theory"

https://www.nature.com/articles/s41598-020-65976-0

Obviously material with 1/2" ceramic spheres is not suited to anything compact like bike locks.
Make the ceramic balls smaller and thickness typical to bike lock and bolt cutters will cut it like butter.
It may have some uses in reinforcing safes or doors (and they have used similar structures for last 100 years.)
Loose washers between steel plates, copper layers, ceramic balls etc etc.

[Doozer]

I dunno,
I have a 5 foot long Ajax rigging bar with a pointy end
and I don't think any bicycle lock is a match for it.
Ajax bars are pretty much the Shinola of rigging bars.

--Doozer

[Paul Alciatore]

So lye! A small bottle of lye and there goes your bike chain. ... and door. ... and whatever.

You just need the right thing to "cut" it.

Sounds like just another advertising balloon. A flag up the flagpole and nobody is saluting.

[Doozer]

At least we will always have petroleum jelly.

-D