Making Ultrastiff and Light Nanomaterials
So often the two things we desire come in conflict with each other, with one example being the need for something strong and light. For large structures, this can be and has been accomplished by using geometries that are open to the air without sacrificing stiffness. Translating this to a microscale has been a challenge for many years though, but researchers at MIT and Lawrence Livermore National Laboratory have recently 3D printed such a special structure.
As the geometry of the structure could be determined mathematically, we have known how a microscale, ultrastiff structure would look for over a decade. The problem has been finding a way to assemble such a small structure. One group, also at MIT, suggested an assembly system that would rely on robots to build the structure from flat panels, but the robotics have not been developed yet. Instead these researchers used projection microstereolithography, which is a 3D printing process that can print with very high precision. The resulting sample structures were able to hold a load 160,000 times their own weight, and roughly 400 times more than a counterpart of similar density.
These stiff, strong, and light microstructures could prove invaluable in systems destined for space, where weight is critical. They could also see use in batteries, as a means to lower the weight of our portable devices.