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New lightweight material is stronger than steel

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Re: New lightweight material is stronger than steel

#151

Post by T-A »

tomrod wrote: post #95

Any time I see one of these numerous claims, I apply the following question set: [1] What are the other metrics to consider? Compression, shear, tensile, and so on (another comment mentions this) [2] What are the expected production costs? [3] Are the costs internalized for production? (I.e. no more teflon ecodisasters) [4] Where should it be used? "Anything" can be "stronger" than "steel" -- it matters what the use…

> Lasers are great to send signals, but we don't want to establish worldwide mesh protocols with it

https://earthsky.org/space/spacex-lasers-will-define-next-st...

Re: New lightweight material is stronger than steel

#152

Post by rini17 »

omegaworks wrote: post #62
montjoy wrote: post #2

> and can be easily manufactured in large quantities That seems promising. I have a couple of concerns - Can it be recycled? - How are new materials like this tested for toxicity?

The article mentions that it's melamine, which we currently find in Magic Erasers. It isn't recyclable or biodegradable, but seems to be non-toxic enough to be a regular fixture in the household cleaning arsenal. It would be far better to use it as (long-lived) building material than as a sponge that quickly degrades and gets rinsed down the drain. 1. https://livegreen.recyclebank.com/column/because-you-asked/w...

Melamine is in widespread use for kitchen furniture surfaces. It is not recyclable, usually it's landfilled or burned.

Re: New lightweight material is stronger than steel

#153

Post by albrewer »

bungle wrote: post #102
albrewer wrote: post #97

Earlier quoted context omitted.

> steel can work perpetually with deformations under a certain threshold[*] [*] Within a temperature range of about ~-30 °C to ~400 °C. Below that and the toughness goes way down so that it's prone to cracking. Above that and carbon starts to work its way into all those crystal structure discontinuities, preventing some percentage of the strain from being relieved each stress cycle (the "creep range"). That's just fo…

> Within a temperature range of about ~-30 °C to ~400 °C. If the new material is plastic-like, it may have worse issues here?

Maybe? PTFE (Teflon) has a melting point around 325 °C; this plastic could be higher. The point of my comment was to qualify what the person above me stated.

Re: New lightweight material is stronger than steel

#154

Post by kazinator »

TheSpiceIsLife wrote: post #145
kazinator wrote: post #48

Lots of old lightweight materials show tensile strength greater than steel. For instance, oh, nylon fiber is stronger than some steels, and way less dense: https://en.wikipedia.org/wiki/Ultimate_tensile_strength#Typi... One kind of steel, "ASTM steel" comes in at 400-500 MPa; nylon fibers at 900. Check out the Bamboo entry in the table. Human hair is also impressive.

BIS80 is a structural steel who's formula is owned by Bisalloy and produced under license by steel manufacturers. BIS80 has a yield strength in excess of 620 Mpa, and an ultimate tensile strength in the range 720 to 930 Mpa. See here for more info https://www.bisalloy.com.au/wp-content/uploads/2020/06/BISAL... BIS100 has a yield strength around the 890 MPa mark, and an ultimate tensile strength in the range 940 to 11…

FWIW, that Wikipedia table lists several steels which have a much higher ultimate tensile strength.

Re: New lightweight material is stronger than steel

#155

Post by upsidesinclude »

This is a coating or a thin film, so far Stronger than steel doesn't mean much of anything, it's just a catchy headline for non engineers. This finding is not important because it's 'stronger that steel' It's a big deal because it's the first time someone has produced a 2D polymer, a sheet polymer, instead of a strand, 1D. 1D polymers are used in everything: textiles, rope or anything with plastic fibers, paints and epoxy, etc

Re: New lightweight material is stronger than steel

#156

Post by TheSpiceIsLife »

kazinator wrote: post #154
TheSpiceIsLife wrote: post #145

Earlier quoted context omitted.

BIS80 is a structural steel who's formula is owned by Bisalloy and produced under license by steel manufacturers. BIS80 has a yield strength in excess of 620 Mpa, and an ultimate tensile strength in the range 720 to 930 Mpa. See here for more info https://www.bisalloy.com.au/wp-content/uploads/2020/06/BISAL... BIS100 has a yield strength around the 890 MPa mark, and an ultimate tensile strength in the range 940 to 11…

FWIW, that Wikipedia table lists several steels which have a much higher ultimate tensile strength.

I see that now I've opened it ;)

I'm familiar with the Bisalloy steels because I have them here right in front of me (metal fabricator by trade and laser cutter operator past 8 years).

Re: New lightweight material is stronger than steel

#157

Post by hrjet »

kardos wrote: post #114
riskable wrote: post #111

I can't believe no one has mentioned this: The researchers claim this material is completely impervious to gasses . Does that mean we've finally got a way to store hydrogen without having it constantly leaking away?

And is that strength enough to put vacuum airships back on the menu?

I would be also interested in mini vacuum packets, that one could strap to their car or backpack, and make it a touch lighter.

Just imagine the energy savings!

Re: New lightweight material is stronger than steel

#158

Post by toss1 »

adrian_b wrote: post #85
cellis wrote: post #74

Earlier quoted context omitted.

Your answer illustrates why, after all these years, HN is still one of the best places to lurk. As someone who forgot most of what he learned in HS chemistry, and didn’t take any collegiate courses, what material would you recommend to learn about this stuff?

I am sorry but I cannot give a good recommendation as some years have passed since I have last searched for chemistry books in this domain. If you go to Amazon and you search, e.g., for "Polymer Chemistry" and for "Materials Chemistry", you will find much more than 100 books. However I do not know which are the best among the recent books. A less risky way than ordering such a book, and finding after paying for it th…

Thx for the Library Genesis pointer - looks like a fantastic resource!

Re: New lightweight material is stronger than steel

#159

Post by toss1 »

solarmist wrote: post #130
kardos wrote: post #125

Earlier quoted context omitted.

https://en.m.wikipedia.org/wiki/Vacuum_airship Like a blimp but with a rigid balloon filled (ha ha) with vacuum instead of a light gas. The article is saying it's a polymer so I'm guessing it doesn't have the right rigidity, ie, the stronger than steel bit must be with respect to a different strength measure

....wow, that is the most counter-intuitive idea I've seen in a long time! A helium balloon makes sense, it's lighter than air so it floats, duh. Well, what's lighter than that? Nothing (vacuum)! It's such a dumb, but correct answer that I had a hard time wrapping my head around it. Yup, theoretically a vacuum would be extremely buoyant if we could put it in a light enough structure.

>>if we could put it in a light enough structure

And there's the problem.

Containing a gas with pressure equivalent to the outside air requires just a membrane. Storing a vacuum requires a container that can resist external pressure of ~ 14 psi. It scales very badly.

This also creates an insane amount of stored energy in the stress on the shell. Here's a couple of videos of vacuum crushing steel tanker railroad cars [0] [1]. Of course that size doesn't even begin to scale up to the level of vacuum that would be required to buoyancy in the earth's atmosphere.

[0] https://www.youtube.com/watch?v=VS6IckF1CM0 [1] https://www.youtube.com/watch?v=yBq5uapC-e0

I'd think the only way to do it might be to have many small hollow spheres contained in a net or something, but the trick would be for each one to be light enough to be positively buoyant...

Re: New lightweight material is stronger than steel

#160

Post by toss1 »

soperj wrote: post #8

Wonder if it work as a rebar replacement that doesn't rust.

There are already very good non-steel rebar - fiberglass. Many manufacturers, easily searchable. I'm astonished it hasn't completely taken over the construction industry, as rusting steel rebar expands and destroys the concrete it is supposed to be reinforcing (concrete is great in compression, lousy in tension).
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