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New lightweight material is stronger than steel

news.mit.edu

11–20 of 162 posts

Re: New lightweight material is stronger than steel

#11

Too bad the article does not actually say what the material is made out of. Does this beat UHWMPE? Because UHMWPE is already damn strung stuff for its weight. But the big downside being that because it is so damn dense it cannot be thermoformed (the big plus being that it also has a huge range of temperature resistance) edit: Correction, it looks like they call it "polyaramide" which sounds like it is similar to Aram…

> For the monomer building blocks, they use a compound called melamine, which contains a ring of carbon and nitrogen atoms. Under the right conditions, these monomers can grow in two dimensions, forming disks. These disks stack on top of each other, held together by hydrogen bonds between the layers, which make the structure very stable and strong.

Re: New lightweight material is stronger than steel

#12

Too bad the article does not actually say what the material is made out of. Does this beat UHWMPE? Because UHMWPE is already damn strung stuff for its weight. But the big downside being that because it is so damn dense it cannot be thermoformed (the big plus being that it also has a huge range of temperature resistance) edit: Correction, it looks like they call it "polyaramide" which sounds like it is similar to Aram…

The article says it is a melamine polymer.

Re: New lightweight material is stronger than steel

#14
Can't wait for 3D printed parts made out of this stuff.

> the new material’s elastic modulus — a measure of how much force it takes to deform a material — is between four and six times greater than that of bulletproof glass. They also found that its yield strength, or how much force it takes to break the material, is twice that of steel, even though the material has only about one-sixth the density of steel.

That's going to make for some fun prints.

Edit: density of steel is 7.85 g/cm3 and 1/6 of that is 1.3 which makes it less dense than wood! (1.5 g/cm3) It floats!

Re: New lightweight material is stronger than steel

#16

Can't wait for 3D printed parts made out of this stuff. > the new material’s elastic modulus — a measure of how much force it takes to deform a material — is between four and six times greater than that of bulletproof glass. They also found that its yield strength, or how much force it takes to break the material, is twice that of steel, even though the material has only about one-sixth the density of steel. That's g…

It would still sink as water has a density of 1, depending. I think your lookup for wood's density gave you a number belonging to a hardwood.

Re: New lightweight material is stronger than steel

#17
post #8

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

Just coat the rebar, one of its properties is that it's impermeable to liquids and gases.

If it's stronger & lighter than steel and produces less CO2 than steel manufacturing...

Re: New lightweight material is stronger than steel

#18
post #16

Can't wait for 3D printed parts made out of this stuff. > the new material’s elastic modulus — a measure of how much force it takes to deform a material — is between four and six times greater than that of bulletproof glass. They also found that its yield strength, or how much force it takes to break the material, is twice that of steel, even though the material has only about one-sixth the density of steel. That's g…

It would still sink as water has a density of 1, depending. I think your lookup for wood's density gave you a number belonging to a hardwood.

You're right, but it is close. Add some air bubbles and it would be buoyant.

Re: New lightweight material is stronger than steel

#19
post #8

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

Just coat the rebar, one of its properties is that it's impermeable to liquids and gases.

That doesn't help if it expands differently from the rebar and concrete. One of the advantages of rebar is that it has a similar coefficient of thermal expansion so when there are temperature changes the concrete and rebar expand and contract in sync and don't have stresses from that.

Re: New lightweight material is stronger than steel

#20
post #17

Earlier quoted context omitted.

Just coat the rebar, one of its properties is that it's impermeable to liquids and gases.

If it's stronger & lighter than steel and produces less CO2 than steel manufacturing...

Forgot the most important part, is it cheaper than steel?
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