Smallest Ever Lattice Structures of Unprecedented Strength
|Fig. 1: This carbon nanolattice, with struts only 970 nm long is not only the smallest lattice structure yet reported but sets new standards for high strength at low density.
(Jens Bauer) Polymeric microlattices have been fabricated by means of a Photonic Professional system, and subsequently they were transformed to glassy carbon by pyrolysis. The pyrolysis of polymeric microlattices was shown to overcome present resolution limits and create ultra-strong nanolattices with single struts shorter than 1 µm and diameters as small as 200 nm (Fig. 1).1
During this heating treatment in vacuum the lattices shrank isotropically by 80% (Fig. 2), representing a world record: The smallest lattice structures produced until today! These nanolattice materials exhibit effective strengths up to 1 GPa at a density well below that of liquid water. Therefore, diamond remains the only bulk material with a notably higher strength-to-density ratio.
Glassy carbon nanolattices represent a significant step forward in the field of lightweight mechanical metamaterials; ultimately, their emergence may yield a new age of stronger, tougher, lighter and more durable materials.2 Pushing full 3D patterning further into the nanoscale by pyrolysis, promises benefits from many physical phenomena with great potential for metamaterials in general. Imagine, if metamaterials in other fields, for example in optics, could be scaled down by a factor of five in the same way!
Don't miss this impressive movie about the uniaxial in-situ compression test of a carbon nanolattice!
Fig. 2: By pyrolysis 3D-printed polymeric microlattices isotropically shrink by 80% and transform to glassy carbon nanolattices.
This contribution was provided by our customer Jens Bauer, University of California, Irvine (US).
 Approaching theoretical strength in glassy carbon nanolattices
Bauer, J., Schroer, A., Schwaiger, R. and Kraft, O.
Nature Materials (2016), DOI: 10.1038/nmat4561
 Mechanical metamaterials: Smaller and stronger
Li, X. and Gao, H.
Nature Materials (2016), DOI: 10.1038/nmat4591