3 ms·

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 b

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!

gp 5y ago
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.
- throwaway4aday 5y ago
  You're right, but it is close. Add some air bubbles and it would be buoyant.
  - HPsquared 5y ago
    I mean technically a submarine is just a bunch of steel and one big air bubble.
    - throwaway4aday 5y ago
      It's all about the size of the air bubble.
blix 5y ago
It's hard to say without reading the paper itself, but in general one should be skeptical of claims that such-and-such material is stronger than steel. The properties that make steel interesting are not its elastic modulus or yield strength. This material is probably closer to graphite (which beats steel in elastic modulus and yeild strength) than something you would actually want to use in a structural application. It will probably be ~very~ difficult to print.
- sdmike1 5y ago
  I'm curious, in that case what properties do make steel interesting?
  - metal_am 5y ago
    It's dirt cheap and incredible versatile. It has many different crystal structures that can give you an incredibly wide range of properties. General purpose mild steel used in buildings. Stainless steel that resists corrosion. Maraging steels used in aerospace. Also, the high modulus is interesting. Some components are stiffness limited such that you couldn't use aluminum or titanium even if you wanted.
  - kragen 5y ago
    Well, its elastic modulus and yield strength are pretty important, actually. Being stiff and strong is pretty fundamental to a lot of its uses. It's stiffer and stronger than most other everyday materials and virtually all everyday plastic materials. Glass, quartz, alumina, zirconia, and porcelain are stiffer than steel, and glass can be stronger, but they're all brittle rather than plastic, which is pretty inconvenient and often makes them very weak in tension. Wood, most other fired clay, aluminum, brass, nearly all organic polymers, mica, cotton, dirt, etc., are much floppier and weaker than steel. But there are a lot of metals that are somewhat stiffer and stronger than steel, like chromium, platinum, and tungsten, while still being somewhat plastic. The great advantage that steel has over them is that it's unbelievably cheap. It's even cheaper than brass, bronze, and lead! Plasticity (ductility and malleability) is important for a couple of reasons. First, as I mentioned above, it greatly increases the fraction of the material's theoretical strength you can get in practice. Second, it allows you to form the material instead of cutting it to shape. That's the property you're using when you wrap a sandwich in aluminum foil or tie a gate shut with baling wire. You can't do that with porcelain foil or porcelain rod. Third, ductile failure happens gradually rather than suddenly, which is important in some cases. The other really interesting thing about steel is that it's hardenable. This is very significant because cutting and forming hard things is hard. So it's routine to cut or form steel in its soft state to get more or less the shape you want, harden it, and then grind it and maybe lap it to the precise shape you want. Grinding and especially lapping can be very precise and cut very hard materials, but they're very slow processes. Finally, steel can withstand much higher temperatures than organic materials, or even most other common metals. These are, I think, the major reason why steel has so extensively displaced what Andrew Carnegie liked to call "inferior materials".
robbedpeter 5y ago
It's a thermoset plastic - melamine - and not very suitable for either resin or thermoplastic printing. It looks like polarized light is part of the polymerization process, to get 3d linkages, so even if you could print, you'd only get super strong layers, not necessarily strong overall prints.
woeirua 5y ago
It always amazes me at how many people don't really understand how buoyancy works.
- cypherpunks01 5y ago
  "When disagreeing, please reply to the argument instead of calling names."
- ummonk 5y ago
  I mean, if you stuck it in a puddle of liquified hardwood, maybe it would float.
loeg 5y ago
How does this compare with carbon fiber-epoxy laminate for elastic modulus? I don't have a ballpark figure for bulletproof glass. Looks like a typical carbon fiber laminate has similar, if slightly higher density (around 1.5 g/cm3).
- deleted 5y ago
  [deleted]

gp 5y ago

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.

throwaway4aday 5y ago
You're right, but it is close. Add some air bubbles and it would be buoyant.
- HPsquared 5y ago
  I mean technically a submarine is just a bunch of steel and one big air bubble.
  - throwaway4aday 5y ago
    It's all about the size of the air bubble.

blix 5y ago

It's hard to say without reading the paper itself, but in general one should be skeptical of claims that such-and-such material is stronger than steel. The properties that make steel interesting are not its elastic modulus or yield strength. This material is probably closer to graphite (which beats steel in elastic modulus and yeild strength) than something you would actually want to use in a structural application. It will probably be ~very~ difficult to print.

sdmike1 5y ago
I'm curious, in that case what properties do make steel interesting?
- metal_am 5y ago
  It's dirt cheap and incredible versatile. It has many different crystal structures that can give you an incredibly wide range of properties. General purpose mild steel used in buildings. Stainless steel that resists corrosion. Maraging steels used in aerospace. Also, the high modulus is interesting. Some components are stiffness limited such that you couldn't use aluminum or titanium even if you wanted.
- kragen 5y ago
  Well, its elastic modulus and yield strength are pretty important, actually. Being stiff and strong is pretty fundamental to a lot of its uses. It's stiffer and stronger than most other everyday materials and virtually all everyday plastic materials. Glass, quartz, alumina, zirconia, and porcelain are stiffer than steel, and glass can be stronger, but they're all brittle rather than plastic, which is pretty inconvenient and often makes them very weak in tension. Wood, most other fired clay, aluminum, brass, nearly all organic polymers, mica, cotton, dirt, etc., are much floppier and weaker than steel. But there are a lot of metals that are somewhat stiffer and stronger than steel, like chromium, platinum, and tungsten, while still being somewhat plastic. The great advantage that steel has over them is that it's unbelievably cheap. It's even cheaper than brass, bronze, and lead! Plasticity (ductility and malleability) is important for a couple of reasons. First, as I mentioned above, it greatly increases the fraction of the material's theoretical strength you can get in practice. Second, it allows you to form the material instead of cutting it to shape. That's the property you're using when you wrap a sandwich in aluminum foil or tie a gate shut with baling wire. You can't do that with porcelain foil or porcelain rod. Third, ductile failure happens gradually rather than suddenly, which is important in some cases. The other really interesting thing about steel is that it's hardenable. This is very significant because cutting and forming hard things is hard. So it's routine to cut or form steel in its soft state to get more or less the shape you want, harden it, and then grind it and maybe lap it to the precise shape you want. Grinding and especially lapping can be very precise and cut very hard materials, but they're very slow processes. Finally, steel can withstand much higher temperatures than organic materials, or even most other common metals. These are, I think, the major reason why steel has so extensively displaced what Andrew Carnegie liked to call "inferior materials".

robbedpeter 5y ago

It's a thermoset plastic - melamine - and not very suitable for either resin or thermoplastic printing. It looks like polarized light is part of the polymerization process, to get 3d linkages, so even if you could print, you'd only get super strong layers, not necessarily strong overall prints.

woeirua 5y ago

It always amazes me at how many people don't really understand how buoyancy works.

cypherpunks01 5y ago
"When disagreeing, please reply to the argument instead of calling names."
ummonk 5y ago
I mean, if you stuck it in a puddle of liquified hardwood, maybe it would float.

loeg 5y ago

How does this compare with carbon fiber-epoxy laminate for elastic modulus? I don't have a ballpark figure for bulletproof glass. Looks like a typical carbon fiber laminate has similar, if slightly higher density (around 1.5 g/cm3).

deleted 5y ago
[deleted]