
Proteus Technology: New Material Is Strong, Light and Non-Cuttable - abeld
https://scitechdaily.com/proteus-technology-new-material-is-strong-light-and-non-cuttable/
======
Jedd
> The freefall of grapefruit from 10 m does not damage the pulp[1] because
> pomelo peel consists of vascular bundles and an open-pored cellular
> structure with the struts made of parenchymatic cells.

I have a Marsh grapefruit tree, fruiting now (southern hemisphere) as it
happens, and I note that it produces particularly pithy progeny. (Ignoring for
the moment that Pomelo is one of the parents of the modern grapefruit.)

I don't have a convenient 10 metre drop to test this, and while I have no
reason to doubt the veracity of this citation, I'm now consumed with curiosity
why this plant has evolved to have this feature.

I expect it's quite an expensive adaptation, and given that modern specimens
are the result of a lot of cross-breeding over the years to have juicier pulp
and a lower ratio of skin/pith to pulp (ie. reduced resistance to damage) it
presumably was even more expensive in ancestor plants.

Standard fruit purpose is to have animals unwittingly propagate the plant --
entice something to eat the fruit, and some time / distance later, deposit the
seeds in a fertiliser ball. How does protecting the pulp from these kind of
damage assist with that -- unless ancestor trees were spectacularly tall, and
ancestor consumers fantastically fastidious on fruit quality.

[1]
[https://doi.org/10.1088%2F1748-3190%2F11%2F4%2F045002](https://doi.org/10.1088%2F1748-3190%2F11%2F4%2F045002)

~~~
ryan_j_naughton
> produces particularly pithy progeny

> fantastically fastidious on fruit quality

Great alliterations. Great writing all around. This just made my night.

~~~
danicgross
Seconded. This could have been written by Churchill.

~~~
DoofusOfDeath
Actual Churchill quote would be "My dear you are inedibly bitter, but tomorrow
I shall be sober and you will still be inedibly bitter."

~~~
dang
Not Churchill, alas.
[https://quoteinvestigator.com/2020/06/28/drunk/](https://quoteinvestigator.com/2020/06/28/drunk/)

------
mindfulhack
This non-cuttable metal material sounds extremely useful:

> "Security applications such as doors or barriers (as protection from
> forcible entry attacks) are obvious ones. However, our material technology
> could also be useful for enhancing the cutting resistance of shoe soles or
> protective clothing. Workers could benefit from non-cuttable elbow pads or
> forearm guards in environments with industrial tools."

As someone who cares so much about digital security, physical security feels
good.

~~~
db48x
This material is completely unsuited for making shoe soles or elbow pads; it's
a two-inch-thick plate of aluminum foam with half-inch ceramic spheres
embedded in it. Around that they welded steel plates to give it a uniform
surface.

It'd make a very heavy but uncuttable door, but you can't make hinges or locks
out of it. It would be a good material to make safes out of; those already
have thick walls of composite materials designed to blunt drill bits.

~~~
throwaway9d0291
I think that's a premature judgement.

Is there any reason to think that it's impossible to scale it down? e.g. for
PPE, 5mm ceramic spheres in a 1cm-thick Aluminimum foam with some 1mm steel
plates on either side?

~~~
db48x
Yes, there is. They hypothesize that this material works because the ceramic
spheres vibrate inside the flexible matrix of the aluminum foam, damaging the
grinding wheel. A thinner foam will have less ability to flex, and smaller
spheres will be have less momentum to use against the wheel.

Plus, if you watch the video of them grinding the material ([https://static-
content.springer.com/esm/art%3A10.1038%2Fs415...](https://static-
content.springer.com/esm/art%3A10.1038%2Fs41598-020-65976-0/MediaObjects/41598_2020_65976_MOESM1_ESM.mov)),
you can see that the grinding wheel penetrates over half an inch before it
begins to be destroyed.

------
trhway
>ceramic spheres encased in a cellular aluminum structure

sounds like the modern "ceramic in a metal matrix" tank armor:

[https://en.wikipedia.org/wiki/Chobham_armour](https://en.wikipedia.org/wiki/Chobham_armour)

"The (pulverised) ceramic also strongly abrades any penetrator. Against
lighter projectiles the hardness of the tiles causes a "shatter gap" effect: a
higher velocity will, within a certain velocity range (the "gap"), not lead to
a deeper penetration but destroy the projectile itself instead."

From the article on the material

"Water jets were also found to be ineffective because the curved surfaces of
the ceramic spheres widen the jet, which substantially reduces its speed and
weakens its cutting capacity."

Not just water jet, the ceramic/metal armor withstands even shaped charge jet
:

"Because the ceramic is so brittle the entrance channel of a shaped charge jet
is not smooth—as it would be when penetrating a metal—but ragged, causing
extreme asymmetric pressures which disturb the geometry of the jet, on which
its penetrative capabilities are critically dependent as its mass is
relatively low. This initiates a vicious circle as the disturbed jet causes
still greater irregularities in the ceramic, until in the end it is defeated.
The newer composites, though tougher, optimise this effect as tiles made with
them have a layered internal structure conducive to it, causing "crack
deflection".[2] This mechanism—using the jet's own energy against it—has
caused the effects of Chobham to be compared to those of reactive armour."

~~~
LoSboccacc
it's more similar to older composite armour, the t64 used something similar
before they switched to the multilayer armour with glass reinforced plastic

[https://m.imgur.com/NA8gcCE](https://m.imgur.com/NA8gcCE)

It was abandoned not because ineffectiveness but because construction
difficulties, uniformity of the embedded spheres was hard to maintain

------
teruakohatu
This could be a revolution in bike locks. Right now compact battery powered
cutting tools can remove just about any bike lock quickly and can easily be
concealed.

~~~
sudosysgen
This is an absolutely amazing innovation, but bike thieves have already
progressed to using powder-actuated pistons in order to break the internal
mechanism of a lock. Much faster and easier than cutting anything.

~~~
mattigames
Locks should have a layer of explosive material inside, so firing the powder-
actuated tool (PAT) may ignite the explosives and destroy the PAT itself, and
it would help too by making some very strong noise so people may hear
something is going on.

~~~
sudosysgen
Are you going to make that explosive sensitive to shocks? Otherwise, how is it
going to ignite? And if you would do so, you realize how dangerous that is,
right?

------
abiogenesis
> The blade is gradually eroded, and eventually rendered ineffective as the
> force and energy of the disc or the drill is turned back on itself, and it
> is weakened and destroyed by its own attack.

What about an angle grinder disc made of this new material?

~~~
hwillis
It would probably not be very good at cutting, and would just get very hot.
Just because the blade doesn't wear away doesn't make it good at cutting.

One way to make something resist abrasives is for it to be/sustain very high
temperatures. If you can survive a hotter temperature than the abrasive (quite
low for diamond, higher for sapphire) then it will be much less effective.

~~~
taneq
Pretty sure once this new material gets hot enough the aluminium substrate
will melt and it'll cut just as well as anything else.

~~~
hwillis
You'd need direct heating, a conventional blade still would not work. The
alumina spheres hold off the cutting edges and block heat flow from hotspots.
A small amount of aluminum foam will melt, but once it's far enough away from
the hot zone it'll just serve to conduct heat away from the ceramic much more
rapidly than it otherwise would.

------
joe-collins
I feel like it says a lot about the HN audience that the biggest reply chain
is about bike locks, of all things.

~~~
IshKebab
Why? Bike locks are surely the most common thing people have experience of
being cut that they don't want to be cut.

~~~
SV_BubbleTime
Did anyone actually read the article? The aluminum foam material has to be
thick and the ceramic beads are large.

Also, even if you just looked at the angle grinder video, you can see the
claims aren’t really as presented. It’s very cutable, it just happens to
eventually dull the cutter eventually. That’s what, a 2” billet they have
there?

For their demo on a similar thickness steel plate, I think that most people
would have an extremely hard time getting that far in 17-4PH steel let alone
SS6xx like Inconel or any one of 100 different steels.

Mostly you would stop from boredom even in a world where the grinder wasn’t
similarly full or broken by the time you gave up.

~~~
IshKebab
Yes I did watch the video, and yes I agree it would be fairly useless for bike
locks. Though there is a very expensive bike lock that has an aluminium
surround the try to foil small angle grinders (the idea is that it is too
thick for the discs to get through). Would be useful for that.

------
exabrial
One may need to use an angle grinder correctly in a video to convince me. The
demo where they plunge the angle grinder straight into the material is no
different than the effect on hardened steel. Typically you would start at an
edge to minimize the contact area of the cut. That's why lock shackles are
rounded.

~~~
SV_BubbleTime
Yea. I can absolutely guarantee they wouldn’t get nearly as far as they did
with a really hard steel like 600-series stainless (Inconel).

I’m certain this is a novel approach with their “jelly filled with nuggets”
but it’s still jelly... let me know when they embed nugget in steel.

~~~
jeffreyrogers
I think they are cutting into the steel plate that they welded to it. Doesn't
look like they get that far into the actual material. I agree with the point
about using the grinder correctly though.

~~~
SV_BubbleTime
You do not (cannot) weld steel to aluminum.

This looks like aluminum billet to me. And other than the grinder stopping, it
looks like it’s cutting exactly like aluminum.

~~~
jeffreyrogers
Sure, it doesn't really matter if it is steel or aluminum. They are cutting
into the plate that is welded to the material. It still appears to stop once
it gets through the plate.

------
steffan
My first thought was "New bike lock material"

My second was:

"New non-cuttable bike lock defeated by ______"

{freezing, shock, heat, _ }

~~~
mparlane
More likely it will be picked rather than cut at that point.

~~~
josephg
Luckily for us, most people who are very good at lock picking (or good at
learning new skills) can find better work that becoming a bike thief. Making
bikes harder to steal results in fewer stolen bikes.

------
ummonk
I wish there were a way to get a sample of this to the lockpickinglawyer.

~~~
tootie
I'm guessing he'd bust out a blowtorch and make short work of it.

~~~
Godel_unicode
Or just pick the (literal weak link in the chain) cheapo lock attached to it.
I'm pretty exhausted from listening to people boast about the amazing lock
they put in their door, which has full-length windows on both sides. Or their
super sturdy door with a generic kwikset lock. The evergreen penetration
testing motto is appropriate here: the goal is simply to get on the other side
of the door.

------
waffle_ss
> _... hardness may not be a fundamental property of a material but rather a
> composite one including yield strength, work hardening, true tensile
> strength, modulus of elasticity, and micro properties such as strength of
> atomic bonds._

Now that is pretty interesting.

It seems they tuned the material to resist the angle grinder, drill and water
jet but it would be interesting to see its ballistic resistance.

~~~
hinkley
I'm not sure why anyone would want cut resistant shoe soles, but I know lots
and lots of people who want _puncture_ resistant shoe soles. Isn't that a
similar process to ballistics?

I note that they didn't really cover that territory, and wonder if that was
lack of facilities or avoiding the tough questions.

~~~
catalogia
> _Isn 't [puncture] a similar process to ballistics?_

Maybe in a sense, but I think not really. Bullet-proof vests aren't
necessarily (usually?) stab proof. (And vice-versa of course.)

------
abeld
Link to scientific paper:
[https://www.nature.com/articles/s41598-020-65976-0](https://www.nature.com/articles/s41598-020-65976-0)

------
nwallin
Can someone define "cuttable" and "non-cuttable" in this context?

~~~
liability
It's resistant to angle grinders and drills.

------
ars
Also submitted here:
[https://news.ycombinator.com/item?id=23903596](https://news.ycombinator.com/item?id=23903596)

------
cl3misch
I can't see the improvement of this vs. walls of high end personal safes. They
have used mixed material walls for ages, made from some hard small component
(e.g. ceramic) embedded in a more flexible mass (hard rubber).

Being accepted in SciRep this material has to have some merit but I am unable
to see it.

Is the structure even scalable to smaller objects? The other comments talking
about bike looks did not read the paper it seems.

------
raverbashing
I'm not sure "non-cuttable" is the best description, it is cuttable, but it
messes the tools

"Cutting resistant" might be a better description, and it is an interesting
material regardless

Sounds like it works for applications where you need something to absorb
"stopping" energy but without wearing out (too much)

~~~
IshKebab
Agreed - that angle grinder got through it fairly quickly I would say. I mean,
slower than other material, sure. But it still cut it.

------
tsomctl
How about a plasma cutter? I know a plasma cutter will cut through normal
silica. (I cut through some steel plate laying right on top of large gravel.)
Silicon dioxides melting point is 1700 C, and aluminum oxide is 2100 C, a
little higher.

~~~
kbenson
Isn't a plasma cutter actually melting an area out of a material and not
actually cutting it?

~~~
sk5t
It does both!

~~~
kbenson
My point is that if you look at that definition of "cut", it's not just
rendering one item into two pieces, other wise tearing or cracking something
would be cutting it, and those aren't cutting either.

I doubt this material is impervious to shear force, or being lowered in
temperature until it's brittle and cracked. But those aren't methods of
_cutting_.

~~~
Brian_K_White
I don't see the distinction. Everything but shears removes material at the
cut. A plasma cut is no different in that respect from a saw, grinder, water-
jet, laser, torch.

~~~
kbenson
Cutting something with scissors, or in the case of thicker metal a press with
a bit, doesn't remove material. Tearing something in two doesn't remove
material. But you're right, any sawing type cut, as with a grinder, does
remove material.

What I was really getting at though is that if you look at the definition of
"cut" you'll see in most (all?) sources it defines it has being achieved
through a sharp object or tool. I understand that's not often how it's used
colloquially though.

------
yladiz
> The cellular structure showed significant deformability, exceeding 20% of
> engineering strain as expected from previous studies of cellular metals

This only talks about the cellular structure, not the overall material
structure, but would this mean that the material would start to deform under a
heavier strain? Does that mean it would make sense to not use this material
alone, but rather with other materials to make a strong product, e.g. a bike
lock with this material on the outside of a thin but rigid pure metal core?

------
CamperBob2
[https://en.wikipedia.org/wiki/Thermal_lance](https://en.wikipedia.org/wiki/Thermal_lance)

~~~
weregiraffe
That's a cheat code.

------
mikx007
What about cicular saw with diamond blade? You can cut cement, ceramics and
granite with it... What about demolition hammer or hammer drill?

~~~
almost_usual
Looks like a conventional cut off wheel in the video, not a diamond blade.

------
ChuckMcM
Combined with an energy dissipating foam it would make for some interesting
ballistic armor. Especially at 15% the density of steel.

------
spajus
They have used a cheap angle grinder disk, what would have happened if they
took a proper diamond one?

------
blackrock
Interesting. Now this is worthy of a patent.

So the material stops the cutting action, by having air sacs inside itself,
where the particulate inside would melt from the friction, and cause the
cutter blade to jam itself up.

------
rasz
Heard that one before
[https://www.dailymotion.com/video/x2p7a6d](https://www.dailymotion.com/video/x2p7a6d)

------
sigmaprimus
Neat idea, very similar to concept of running a chain through a pipe to
prevent cutting, but in three dimensions. I do wonder what effect freezing
would have on it though.

~~~
gruez
>Neat idea, very similar to concept of running a chain through a pipe to
prevent cutting

People do that? Also, how does it work?

~~~
praptak
The grates that protect prison windows are often made of pipes with a bunch of
loose rods inside. Cutting through the pipe itself is relatively easy, but the
rods inside are unfastened, so they tend to roll under the cutting tools.

Edit: The principle is actually somewhat similar to the anti-drill protection
on door locks - a small disc in front of the lock with a slit that the key
goes through. The disc makes it hard to drill through the lock, because it
spins together with the drill.

------
flippyhead
[https://en.wikipedia.org/wiki/Vibranium](https://en.wikipedia.org/wiki/Vibranium)
!

------
MrLeap
Porous Aluminum eh? Wonder how well it stands up to gallium, or acetylene, or
MAP gas, or a grind wheel instead of a cutoff wheel.

~~~
hwillis
the ceramic inside is alumina, so same material as both a cutoff wheel and a
grinding wheel. They mention that it's not the _best_ purity and hardness, but
it's pretty good.

------
unstatusthequo
Waiting for this to exist in an Abus lock so my storage unit can stop being
broken into my tweakers.

~~~
beenBoutIT
It only protects you from tweakers armed with cutters. Industrious tweakers
with better tools at their disposal might be able to crush it or melt it.

~~~
waste_monk
>industrious tweakers with better tools

They're probably breaking in hoping to steal tools to sell. If they had decent
tools they would have already sold them. It's not impossible but well-equipped
tweakers are far less likely than other kinds of thief.

On the other hand they're batshit crazy enough to try other means, why bother
trying to break into a storage unit when you can chain the door handle to your
(also stolen) car and rip the whole unit door off.

------
fmakunbound
Nothing in there on its electrical properties. Can it be cut using a plasma
cutter?

~~~
repiret
Given that its ceramic beads embedded in aluminum foam, I would guess any
heat-based cutter would make short work of it. But then again, I would also
guess a diamond blade meant for ceramics would go farther than the standard
abrasive cut-off wheel meant for soft metals that they showed in the video.

------
agumonkey
This resists mechanical forces, but what about EDM milling or plasma ?

------
mint2
That’s pretty cool. can it be cut with bolt cutters or such?

------
azinman2
So how do you shape/use it during manufacturing?

~~~
jakeogh
Diagram:
[https://www.nature.com/articles/s41598-020-65976-0/figures/2](https://www.nature.com/articles/s41598-020-65976-0/figures/2)

------
01100011
Aluminum. A highly reactive metal prone to rapid decomposition in household
drain cleaner. Yeah, this isn't going to revolutionize bike locks.

------
greesil
This would be great for bike locks!

~~~
catalogia
I'd bet against it. It seems to hold up well against abrasive tools, but an
aluminum foam with ceramic balls embedded in it doesn't sound like the recipe
for an all around robust lock shackle. How would it stand up against bolt
cutters (shearing cuts, not abrasive cutting), a manually operated hacksaw, or
impact? A hacksaw might have the finesse to thread the gap between the
ceramic.

~~~
FreeFull
My guess is that the hacksaw wouldn't work particularly well, but the bolt
cutters or anything else that just exerts a strong, steady force without much
motion should work. At that point, it shouldn't be any stronger than just
regular aluminium.

------
syllable_studio
Can Proteus be cut by Proteus?

------
zrkrlc
Space elevator?

~~~
flemhans
It’s too heavy

------
epicureanideal
Physical shields for spacecraft?

Bullet proof vests?

Ammunition?

~~~
mod
Motorcycle protective gear.

------
Bobbcatt
Will this work as armor?

~~~
jachee
I believe that answer hinges on whether "cut proof" is the same as "puncture-
proof".

~~~
senectus1
Sword players will still be interested...

~~~
db48x
Not really. Armor made of this material has to be much thicker than ordinary
steel plate. Furthermore, ordinary steel plate is entirely effective against
swords, except at the joints and articulations.

~~~
pmlnr
> entirely effective against swords

Against the immediate cutting, probably. But it also bends. And with bending,
it could damage you really bad, including the part that removing them could
become quite a trouble.

~~~
db48x
True, but cutting is what we're talking about here, and since the material
they've invented in this article is made of aluminum foam, it'll bend even
easier than steel of the same thickness.

------
jupp0r
In Star Trek, they called it transparent aluminium!

~~~
Avamander
That's a real thing:
[https://en.m.wikipedia.org/wiki/Aluminium_oxynitride](https://en.m.wikipedia.org/wiki/Aluminium_oxynitride)

------
cvg
Sounds amazing, but how will we dispose of this? Looks like 760 C is required
to form this. I imagine it will need to be heated above this to dispose of.

~~~
jeppesen-io
Huh? Plenty of things go in landfills that won't go away for many lifetimes

~~~
artonge
Seems legit to ask whether we can prevent adding more things to those
landfills.

~~~
db48x
Like all metal items, this is trivial to recycle by melting it.

