At the Karlsruhe Institute of Technology in Germany (KIT), researchers are using bones as inspiration to create a new, lightweight material using 3D laser lithography.
Bones are lightweight, durable, and able of to withstand a great deal of stress, to a certain point, without breaking. Their strength is due in part to their structure, which is comprised of air pockets and a repeating pattern.
New developments in laser technology and 3D printing have given researchers the tools that they need to materialize the design concepts. At KIT, the research team led by Jens Bauer used special lasers developed by Nanoscribe and a technique called 3D laser lithography, which uses miniscule laser beams and lenses to create structures in the light-sensitive polymer. The polymer was covered in an aluminum-based compound to create a series of bone-like patterns.
Researchers created at least ten different patterns, in an attempt to find a structure that best recreates bones’ durability. They found that some patterns fractured under pressure, while others simply buckled. However, their research didn’t leave them empty handed. Researchers now have multiple options for printing bone-like structures. The researchers found that the strongest material had an internal honeycomb structure; and was coated with a layer of alumina. This structure was able to withstand pressure up to 280 mega pascals, making it the strongest man-made material that is lighter than water.
The researchers published their findings in the Proceedings of the National Academy of Sciences on Monday.
While researchers can now 3D print bone-like structures, these structures can’t be printed at home. The material needed to make a bone imitation requires a printer that is more accurate. The printer needed would have to be accurate down to the single micron. Most 3D desktop printers don’t make it past 100 microns.
This isn’t the first time that bone has been used for inspiration to create a fracture-resistant material, however. Last year, researchers at MIT created fracture-resistant material, on a larger scale though, that a desktop 3D printer can print. The material didn’t integrate to a bone-like structure at a smaller level.
Nanoscribe’s current system creates elements that are tens of micrometers in size. It is thought that as 3D printing and laser technology continue to develop, and material technologies improve, that possibilities for real life applications of strong and lightweight materials will develop as well.