3 ms·

3D-printed "metamaterial" is stronger than anything in nature

51 points by wjb3 3y ago

r14c 3y ago
Integza posted an interesting video about novel applications of porous metal printed parts. Really excited to see how this develops.
j_m_b 3y ago
Strong enough for a space elevator?
- avmich 3y ago
  Not strong enough to survive collisions of satellites with the space elevator.
- DigitalHackOp 3y ago
  Not even close. They optimized for strength-to-weight ratios, which is great for a ton of things, but a space elevator needs insane levels of brute strength. Were not sure the material can exist in our current understanding of physics
  - readthenotes1 3y ago
    "Great for a ton of things" heh
  - Qwertious 3y ago
    Don't forget that space elevators need more than brute strength: they need to be immune to all sorts of cosmic radiation and space debris, they presumably need to be electrically conductive since the elevator carriage will need a lot of power to travel upwards a few thousand KMs before their passengers starve to death, they need to be robust against the elevator carriage's friction, and probably a few other things.
    - _w1tm 3y ago
      > they presumably need to be electrically conductive since the elevator carriage will need a lot of power to travel upwards a few thousand KMs before their passengers starve to death Even a slow space elevator that can only be used for transporting cargo would already be extremely useful. You could even load it with a container filled with life support if you really need to ship living cargo.
  - Turing_Machine 3y ago
    An orbit to ground space elevator would indeed be challenging, but the cable doesn't have to go all the way to the ground to be useful. Shorter tethers have many applications, and those can be made out of non-exotic materials (e.g. Kevlar). https://en.wikipedia.org/wiki/Space_tether https://en.wikipedia.org/wiki/Space_tether There are still challenges, of course.
- beambot 3y ago
  The lattice structures shown in the article are likely optimized for compression strength. Tensile strength is the limiting factor for space elevators. Very different design constraints.
0cf8612b2e1e 3y ago
What kinds of parts are currently made with these of printers? I assume they are slow that it takes really interesting shapes or tolerances to warrant not using traditional manufacturing.
- gravescale 3y ago
  GE's LEAP engine, for example, uses 3D printed parts, I think for the fuel injector nozzles. This is a laser method, but binder jet printing is getting cheaper and easier by the year but it is still fairly slow.
aeonik 3y ago
What temperature does it melt at? I'm curious to know more failure more. I'm also curious how the human immune system reacts to it, though I'm sure it's not known yet.
- rsfern 3y ago
  It’s a titanium alloy (Ti-6-4) that’s commonly used in medical implants, and it probably melts at pretty high temp - the wrought form is used in turbine engine compression disks This is like a 3D printed metal scaffold, in the paper they’re doing compression tests. Probably more likely structural applications than medical I’m guessing https://en.m.wikipedia.org/wiki/Ti-6Al-4V https://en.m.wikipedia.org/wiki/Ti-6Al-4V
  - capitainenemo 3y ago
    https://pubmed.ncbi.nlm.nih.gov/7634595/ https://pubmed.ncbi.nlm.nih.gov/7634595/ ← from a search for qualities searched for in implants. "The primary advantage of TiAlV over CoCrMb is a lower modulus of elasticity. This results in decreased stress shielding and subsequent favorable femoral remodeling." This new material might do well there.. "TiAlV has been shown to achieve excellent bone ingrowth into porous surfaces." Well, given they printed this structure almost as a sponge it probably would do well on that front too.
    - rsfern 3y ago
      To be honest I don’t know too much about the biomedical side, I’m probably jumping to conclusions on what the materials research directions are there - originally I was just going to joke about how you might hope it doesn’t hit its melting temperature if it’s used in a medical implant as it starts to melt around 1600 C
KevinMS 3y ago
It already exists, its called infill
- pbronez 3y ago
  Are you aware of any slicers that implement this tube-grid + plane-grid pattern? Seems doable, but I haven’t seen it yet.
gravescale 3y ago
That stress simulation is very interesting. I wonder would happen if they just filleted all the corners, inside and out. They've added a lot of direct compression "paths" through the vertical web so it's not surprising it's unloaded the corners where the stress used to "go around" the void.
e44858 3y ago
Has anyone tried printing this with an FDM printer?
- rsfern 3y ago
  It’s not that kind of 3D printing, it’s laser powder bed fusion [0]. I don’t know a lot about FDM but I’d be kind of surprised if you could do Ti-64 and get the same mechanical strength (but I’d be interested to know if I’m off base) because I think it’s like metal embedded in polymer that you have to sinter post-build? Compared to basically doing a continuous laser weld with the powder bed method However, here [1] is a cool paper looking at optimizing similar meta material structures using polymer filament printing - if you could do something similar in metal FDM that might be interesting? 0: https://en.m.wikipedia.org/wiki/Selective_laser_melting https://en.m.wikipedia.org/wiki/Selective_laser_melting 1: https://doi.org/10.1126/sciadv.aaz1708 https://doi.org/10.1126/sciadv.aaz1708
  - Turing_Machine 3y ago
    I'm not sure what difference that would make? I mean, obviously metal is going to be stronger than fused plastic, but I gather here that what makes it stronger than normal is the structure. Wouldn't FDM plastic objects made with this structure be stronger than FDM objects made with a more conventional structure? That would be very useful even if it's not as strong as metal. I think I'm going to print up some test pieces and do destructive testing.
    - rsfern 3y ago
      Sorry - I didn’t mean to come off as discouraging, that’s part of why I linked the BEAR paper! I agree in relative terms, I’d think this cellular structure should have better compressive strength than a different structure made of the same material I guess where I’m coming from is that FDM titanium (if you can realistically print that, I don’t know) isn’t going to have the same properties as SLM titanium, so the headline strength (in absolute terms) is probably not achievable in FDM Ti
wpollock 3y ago
I thought limpet teeth were the strongest material known?
bborud 3y ago
Observation: it took longer to respond to the GDPR popup than read the article. And to be frank, I just skimmed/quick read the descriptions of each choice.

51 points by wjb3 3y ago

r14c 3y ago

Integza posted an interesting video about novel applications of porous metal printed parts. Really excited to see how this develops.

j_m_b 3y ago

Strong enough for a space elevator?

avmich 3y ago
Not strong enough to survive collisions of satellites with the space elevator.
DigitalHackOp 3y ago
Not even close. They optimized for strength-to-weight ratios, which is great for a ton of things, but a space elevator needs insane levels of brute strength. Were not sure the material can exist in our current understanding of physics
- readthenotes1 3y ago
  "Great for a ton of things" heh
- Qwertious 3y ago
  Don't forget that space elevators need more than brute strength: they need to be immune to all sorts of cosmic radiation and space debris, they presumably need to be electrically conductive since the elevator carriage will need a lot of power to travel upwards a few thousand KMs before their passengers starve to death, they need to be robust against the elevator carriage's friction, and probably a few other things.
  - _w1tm 3y ago
    > they presumably need to be electrically conductive since the elevator carriage will need a lot of power to travel upwards a few thousand KMs before their passengers starve to death Even a slow space elevator that can only be used for transporting cargo would already be extremely useful. You could even load it with a container filled with life support if you really need to ship living cargo.
- Turing_Machine 3y ago
  An orbit to ground space elevator would indeed be challenging, but the cable doesn't have to go all the way to the ground to be useful. Shorter tethers have many applications, and those can be made out of non-exotic materials (e.g. Kevlar). https://en.wikipedia.org/wiki/Space_tether https://en.wikipedia.org/wiki/Space_tether There are still challenges, of course.
beambot 3y ago
The lattice structures shown in the article are likely optimized for compression strength. Tensile strength is the limiting factor for space elevators. Very different design constraints.

0cf8612b2e1e 3y ago

What kinds of parts are currently made with these of printers? I assume they are slow that it takes really interesting shapes or tolerances to warrant not using traditional manufacturing.

gravescale 3y ago
GE's LEAP engine, for example, uses 3D printed parts, I think for the fuel injector nozzles. This is a laser method, but binder jet printing is getting cheaper and easier by the year but it is still fairly slow.

aeonik 3y ago

What temperature does it melt at? I'm curious to know more failure more. I'm also curious how the human immune system reacts to it, though I'm sure it's not known yet.

rsfern 3y ago
It’s a titanium alloy (Ti-6-4) that’s commonly used in medical implants, and it probably melts at pretty high temp - the wrought form is used in turbine engine compression disks This is like a 3D printed metal scaffold, in the paper they’re doing compression tests. Probably more likely structural applications than medical I’m guessing https://en.m.wikipedia.org/wiki/Ti-6Al-4V https://en.m.wikipedia.org/wiki/Ti-6Al-4V
- capitainenemo 3y ago
  https://pubmed.ncbi.nlm.nih.gov/7634595/ https://pubmed.ncbi.nlm.nih.gov/7634595/ ← from a search for qualities searched for in implants. "The primary advantage of TiAlV over CoCrMb is a lower modulus of elasticity. This results in decreased stress shielding and subsequent favorable femoral remodeling." This new material might do well there.. "TiAlV has been shown to achieve excellent bone ingrowth into porous surfaces." Well, given they printed this structure almost as a sponge it probably would do well on that front too.
  - rsfern 3y ago
    To be honest I don’t know too much about the biomedical side, I’m probably jumping to conclusions on what the materials research directions are there - originally I was just going to joke about how you might hope it doesn’t hit its melting temperature if it’s used in a medical implant as it starts to melt around 1600 C

KevinMS 3y ago

It already exists, its called infill

pbronez 3y ago
Are you aware of any slicers that implement this tube-grid + plane-grid pattern? Seems doable, but I haven’t seen it yet.

gravescale 3y ago

That stress simulation is very interesting. I wonder would happen if they just filleted all the corners, inside and out. They've added a lot of direct compression "paths" through the vertical web so it's not surprising it's unloaded the corners where the stress used to "go around" the void.

e44858 3y ago

Has anyone tried printing this with an FDM printer?

rsfern 3y ago
It’s not that kind of 3D printing, it’s laser powder bed fusion [0]. I don’t know a lot about FDM but I’d be kind of surprised if you could do Ti-64 and get the same mechanical strength (but I’d be interested to know if I’m off base) because I think it’s like metal embedded in polymer that you have to sinter post-build? Compared to basically doing a continuous laser weld with the powder bed method However, here [1] is a cool paper looking at optimizing similar meta material structures using polymer filament printing - if you could do something similar in metal FDM that might be interesting? 0: https://en.m.wikipedia.org/wiki/Selective_laser_melting https://en.m.wikipedia.org/wiki/Selective_laser_melting 1: https://doi.org/10.1126/sciadv.aaz1708 https://doi.org/10.1126/sciadv.aaz1708
- Turing_Machine 3y ago
  I'm not sure what difference that would make? I mean, obviously metal is going to be stronger than fused plastic, but I gather here that what makes it stronger than normal is the structure. Wouldn't FDM plastic objects made with this structure be stronger than FDM objects made with a more conventional structure? That would be very useful even if it's not as strong as metal. I think I'm going to print up some test pieces and do destructive testing.
  - rsfern 3y ago
    Sorry - I didn’t mean to come off as discouraging, that’s part of why I linked the BEAR paper! I agree in relative terms, I’d think this cellular structure should have better compressive strength than a different structure made of the same material I guess where I’m coming from is that FDM titanium (if you can realistically print that, I don’t know) isn’t going to have the same properties as SLM titanium, so the headline strength (in absolute terms) is probably not achievable in FDM Ti

wpollock 3y ago

I thought limpet teeth were the strongest material known?

bborud 3y ago

Observation: it took longer to respond to the GDPR popup than read the article. And to be frank, I just skimmed/quick read the descriptions of each choice.