As one of the hardest materials on earth, diamonds have become the benchmark for many materials science studies, because engineers are working hard to create new hard structures to surpass the best materials in nature. A team at the University of California, Irvine (UCI) has now created a nanoscale carbon lattice with a strength-to-density ratio that exceeds that of diamond.
The new design developed by the UCI research team is called the nanolattice. These porous structures are composed of pillars and scaffolds made of carbon (just like the diamond itself), they are arranged into a three-dimensional lattice with excellent strength-to-strength ratio. For decades, these nanolattices have been based on the use of cylindrically arranged truss designs. UCI researchers attributed their breakthrough to a departure from this tradition, and replaced them with a series of boards.
"The previous beam-based design, although very interesting, was not so effective in terms of mechanical performance," said Jens Bauer, author of the study and UCI mechanical and aerospace engineering researcher. "The new plate-type nanolattice we created is much stronger and harder than the best beam-type nanolattice."
Although this type of plate nano-lattice structure has been theoretically considered to have stronger strength than other designs, it is not easy to manufacture them. The UCI team stated that it has now successfully assembled these theories by adopting a novel method, proving that these theories are correct. This involves a complex 3D printing technique that focuses the laser within the droplets of UV-sensitive liquid resin. This will turn the resin into a solid polymer, which can then be processed into microscopic plates as thin as 160 nanometers. The small holes on the board allow the excess resin to be removed from the finished product, and then heated to 900 ° C (1652 ° F) in a vacuum for one hour, the resin will be pyrolyzed.
According to the team's experiments, the resulting carbon nanolattice is 639% higher in average strength and 522% in average stiffness than the cylindrical beam structure. "Lorenzo Valdevit, professor of materials science and engineering at UCI, said:" Although the theoretical performance of these structures has been predicted before, we are the first to verify that their performance is as good as predicted, and also demonstrates an unprecedented Structural materials for mechanical properties. "
Researchers believe that one of the areas where nanocrystals like this can really work is in the aerospace field, where engineers have been looking for low-density materials that can provide great strength.