The smallest
lattice in the world is visible under the microscope only. Struts and braces
are 0.2 µm in
diameter. Total size of the lattice is about 10 µm. (Photo: J. Bauer / KIT)
(February 2, 2016) 3D
Lattice with Glassy Carbon Struts and Braces of Less Than 200 nm in Diameter
Has Higher Specific Strength Than Most Solids
KIT scientists now present the smallest lattice structure
made by man in the Nature Materials journal. Its struts and braces are made of
glassy carbon and are less than 1 µm long and 200 nm in diameter. They are
smaller than comparable metamaterials by a factor of 5. The small dimension
results in so far unreached ratios of strength to density. Applications as
electrodes, filters or optical components might be possible. (DOI:
10.1038/nmat4561)
“Lightweight construction materials, such as bones and wood,
are found everywhere in nature,” Dr.-Ing. Jens Bauer of Karlsruhe Institute of
Technology (KIT), the first author of the study, explains. “They have a high
load-bearing capacity and small weight and, hence, serve as models for
mechanical metamaterials for technical applications.”
Metamaterials are materials, whose structures of some
micrometers (millionths of a meter) in dimension are planned and manufactured
specifically for them to possess mechanical or optical properties that cannot
be reached by unstructured solids. Examples are invisibility cloaks that guide
light, sound or heat around objects, materials that counterintuitively react to
pressure and shear (auxetic materials) or lightweight nanomaterials of high
specific stability (force per unit area and density).