China Produces Nano Fibre That Can Lift 160 Elephants - and a Space Elevator? (nzherald.co.nz)

Slashdot reader hackingbear quotes the NZ Herald: A research team from Tsinghua University in Beijing has developed a fibre they say is so strong it could even be used to build an elevator to space. They say just 1 cubic centimeter of the fibre — made from carbon nanotube — would not break under the weight of 160 elephants, or more than 800 tonnes. And that tiny piece of cable would weigh just 1.6 grams... The Chinese team has developed a new "ultralong" fibre from carbon nanotube that they say is stronger than anything seen before, patenting the technology and publishing part of their research in the journal Nature Nanotechnology earlier this year...

The space elevator idea has remained in the realm of sci-fi, physical and mathematical models because there has been no material strong enough to make the super-light, ultra-strong cables needed... Now, the Tsinghua team, led by Wei Fei, a professor with the Department of Chemical Engineering, says their latest carbon nanotube fibre has tensile strength of 80 gigapascals [over ten times more than the 7 gigapascals strenth NASA estimated to be required for a space elevator]... Chinese and Russian space scientists, for instance, are working together to find a safe, effective way to lower a fine, feather-light cable from a high-altitude orbit to the ground.
Wei also said his team was trying to get the carbon nanotube fibre into mass production for use in defense -- or to create super fast flywheels in a mechanical battery, which would have 40 times the energy density of a lithium battery.

Comments

Better Article from Ars

[Crashmarik]

https://arstechnica.com/scienc...

While the authors note that this work could find a home in "sports equipment, ballistic armour, aeronautics, astronautics and even space elevators," we're still a long way from any of that. Ideally, rather than synthesizing the nanotubes in centimeter-long chunks, we'd like to have some sort of continual production process. Still, the work is important in that it hints that there is a world beyond micrometer-scale nanotube fragments.

Nice to have my instinct confirmed that there would of been much more noise over this if Ultralong meant kilometers or or at least 10s of meters.

Re:Better Article from Ars

[ShanghaiBill]

there would of been much more noise over this if Ultralong meant kilometers or or at least 10s of meters.

Actually, if a single nanotube is 1 cm, that is enough. The length would be 10M times the diameter, and the Van der Waals attraction between adjacent tubes along their entire length would far exceed the strength of the covalent link between carbon atoms in a tube.

If you were building a space elevator to GEO (36,000 km), the difference is strength between using a fiber constructed from 1 cm tubes and 1 km tubes would be negligible.

Re:Better Article from Ars

[religionofpeas]

How did African elephants end up in China ? They are non migratory.

Re:Better Article from Ars

[Tough Love]

Let's not forget that carbon nanotubes make asbestos look like cotton candy, healthwise. In animal studies, exposure to CNTs induced sustained inflammation, fibrosis, lung cancer following long-term inhalation, and gene damage in the lung.

Re:Better Article from Ars

[CrimsonAvenger]

would of been

"would've been". It's a contraction of "would have been".

It would've been nice if (supposedly) bright, (supposedly) well educated people could spell....

Re:Better Article from Ars

[GameboyRMH]

African or Asian elephants?

Re:Better Article from Ars

[Pinky's Brain]

There seems to be a bit of controversy in what keeps graphite together and what to call the forces, some call it Van Der Waals, some call it metallic bonds ... suffice to say, graphite does keep together. So there is a force there, the same would be true for a bundle of these nanotubes.

Re:Better Article from Ars

[TheRaven64]

Graphite holds together, but only just. Pencils work because a tiny amount of shear force is enough to cause layers of it to come off (and that's the direction that you'd be fighting if you tried to pull two tubes apart that were stuck in this way). A child can pull a lump of graphite apart.

This has always been the problem with potential space-elevator materials. It's relatively easy to make something that's strong enough over a very short distance, but none of the proposed materials can either be synthesised in a single long chunk (yet?) or can be woven together to form a rope that maintains anything like the same tensile strength.

Re:Better Article from Ars

[Pinky's Brain]

The graphene layers in graphite aren't well ordered though and as the original poster said though, the ratio of the length of the fiber to it's thickness is massive ... so small forces might add up. Impossible to say without actually doing experiments (the physical models are too poor to put much faith in).

what connects strong nano fibre & space elevat

[sittingnut]

how was it that first use case imagined for this fibre become space elevator?
aren't there more down to earth already practicable use cases, where this fibre will replace some other fibre because it is better.

Re: what connects strong nano fibre & space el

[Anonymous Coward]

Yes, lifting 160 elephants.

Inquiring minds want to know

[drewsup]

Asian or African elephants, laden or unladen?

Re:Inquiring minds want to know

[ShanghaiBill]

Asian or African elephants, laden or unladen?

African elephants, unladen.

TFA says 160 elephants, or 800 tonnes, or 5000 kg per elephant. That is about the average weight of an African elephant. Females are about 4000 kg and males about 6000 kg, averaging to 5000 kg.

Asian elephants are considerably smaller, averaging about 4000 kg. The only way to average 5000 kg with Asian elephants would be to use all males, but the males tend to be aggressive and difficult to handle, and there is no way you are going to get 160 of them onto a scale.

Re:Inquiring minds want to know

[hackertourist]

Sure there is. Just apply plenty of butter for them to leave footprints in.

Re:Inquiring minds want to know

[morethanapapercert]

I thought you'd need an infinite number of turtles, since "it's turtles all the way down..."

But such a product might be good news for the environment, since we'd have to preserve wet lands and numerous species of turtles in order to have an assured supply of turtles to send into orbit. We don't need to breed any huge numbers of turtles at any given time mind you. Sending up an infinite number of turtles is going to take an infinite amount of time (and energy) no matter how quickly we do it, might as well have a good, solid sustainable program instead of a crash priority thing.

Cross sectional area ?

[Alain Williams]

Quoting volume for a rope is not very helpful. The cross sectional area would be much more interesting for saying how much it can carry.

Re:Cross sectional area ?

[ShanghaiBill]

Quoting volume for a rope is not very helpful.

Indeed. That is one of the stupidest metrics I have seen in a while.

The cross sectional area would be much more interesting for saying how much it can carry.

Well, they do say 80 gigapascals, which means 80 billion newtons per square meter. That is 8 million newtons per square cm, which in earth's gravity is equivalent to supporting ~800,000 kg, or 800 metric tonnes. Which is roughly the weight of 160 elephants.

For a space elevator, an important metric is how much of its own length it can support. Carbon nanotubes have a density of about 2.5 gm/cc. So 800 tonnes is about 3200 km of fiber with a square cm cross section. TFA says that is enough, but that will get you only a tenth of the way to GEO.

Re:Cross sectional area ?

[Solandri]

After seeing load given in elephant weights, I was expecting cross sectional area to be given as a fraction of human hair width, and disappointed when I didn't see it. We could standardize elephants per hair as a new unit of pressure for the media.

Well, they do say 80 gigapascals

Do note that the glass fibers in regular fiberglass have a tensile strength approaching 5 GPa. So regular materials are within an order of magnitude of what's needed for a space elevator. Fiberglass' performance only craters when you have to use resin to hold disparate fibers together. That's the real challenge here - how to extrude a single really-long carbon nanotube, or glue a bunch of them together with minimal loss of strength. One of the reasons the use of metals is so widespread is because their crystalline grains slide against each other until they interlock, self-solving the "glue a bunch of them together" poblem.

Don't Forget

[trabby]

That even when the tech is ready:

"The Space Elevator will be built about 50 years after everyone stops laughing." - Arthur C. Clarke

Re:what connects strong nano fibre & space ele

[sheramil]

Near-invisible, huh? Birds trying to fly through it, coming out in sections.. people brushing against it, losing fingers... yakuza vat-grown ninjas swinging fake thumbs about on a spool of it, cutting people in half...

Re:Space Elephants?

[mentil]

Obviously, Tactical Bombardment Elephants are the secret weapon of the Space Force.

Re:Space elevator in a hurricane

[ShanghaiBill]

A space elevator has to be located on the equator, where there is no coriolis effect, and thus no hurricanes.

Cubic Centimeter?

[thsths]

You are aware that stress is measured in force per area, not elephants per volume?

Re:what connects strong nano fibre & space ele

[gtall]

Imagine the Chinese gift for hyperbole outrunning your common sense.

Re:Cue the anti-China rhetoric

[religionofpeas]

at lease you protecting yourselves from those caravans of migrants hundreds of miles from your borders.

The Uyghurs would like a subscription to your newsletter.

Re: what connects strong nano fibre & space el

[javaman235]

Chinese already did, in the Chinese sci-fi novel Three Body Problem, where the good guys construct something like that to cut a ship into pancake sections to kill the bad guys and recover something inside.

Will await independent verification.

[Chas]

Lots of these Chinese "inventions" turn out to be absolute bunk and cooked results.

Will need to see it peer-reviewed by a country that doesn't reward theft and falsehood in the hard sciences.

Re:what connects strong nano fibre & space ele

[Type44Q]

how was it that first use case imagined for this fibre become space elevator?

It wasn't; the elevator is only for the elephants and they forgot to mention the turtle,

Is it even real?

[Shaitan]

I wouldn't get too excited about fantastic and amazing new developments coming out of China. From my understanding replicability tends to be low.

Imagine a feasible space elevator ...

[Qbertino]

Price to geo-stat orbit: 300 Euros per kilogram or less. Nice. We'd just assemble a massive spaceship and the first trip to mars would be an extended luxury cruise or something like that. Very nice. We'd be casually exploring the solar system and have a permanent residence on mars. Very nice indeed.

AFAIAC China should get right to it.

Re:Space elevator in a hurricane

[ShanghaiBill]

Ideally located there

No. It MUST be located on the equator. It is tethered to a counterweight in orbit. The satellite will trace a great circle around the center-of-mass of the earth. An equatorial orbit is the only orbit that will pull directly upward for the entire orbit.

Most proposals put the base on a barge located in the equatorial Atlantic or Pacific. The barge will make it easy to access and service, and also allow it to move slightly to avoid orbital debris.