So does this mean that at the macroscale, the 3D-printed metal will be 3x as strong? Could this result in a car that's 1/3rd the metal weight?
(I'm guessing "no", but I want to understand why.)
(I'm guessing "no", but I want to understand why.)
The next step would then be special medical applications. For example, as a synthetic material for implants. And there you wouldn't want ultra strength, but a certain bounciness and relatively low density.
Edit: but it is not clear to me, whether this technic can be applied to macroscopical objects at all, or if you would have to do it in steps - and then have structural weaknesses at the connection points.
From my understanding, there are (at least) 3 factors responsible for the high strength
- nanoscale geometry, basically the can 3D print nanoscale truss structures
- nanocrystalline base metal. There are established methods for fabricating bulk nanocrystalline metals [0], but doing it in an additive manufacturing process at bulk scale I think is a totally open question
- they’re getting extra strength from residual porosity in the metal grains (the pores pin dislocations, stopping one of the principal deformation mechanisms [1]). This is a well known phenomenon, but getting uniform nanoscale pore structure sounds really hard, especially in a bulk metal, and extra especially in an additive setting
0: https://en.m.wikipedia.org/wiki/Nanocrystalline_material#