MIT researchers were able to design one of the strongest lightweight materials known. They were able to do this by compressing and fusing together flakes of graphene, which is a two-dimensional form of carbon. This new material is a sponge-like configuration that has a density of only 5 percent and it can have a strength 10 times that of steel!
Graphene, in its two-dimensional form, is thought of as to be the strongest of all known materials. But even until now, they have a difficult time translating this two dimensional strength into useful three-dimensional materials.
The new findings from the research team show that the most important aspects of the new 3D forms is connected to their unusual geometrical configuration rather than the material itself. This means that similar strong, and lightweight materials could be made from different materials by creating similar geometric features.
The research was done by Markus Buehler, the head of MIT’s Department of Civil and Environmental Engineering (CEE) and the McAfee Professor of Engineering; Zhao Qin, a CEE research scientist; Gang Seob Jung, a graduate student; and Min Jeong Kang MEng ’16, a recent graduate.
The team was able to compress small flakes of graphene by combining heat and pressure. This process was able to produce a strong stable structure. The structure resembles some corals and microscopic creatures called diatoms. These shapes have enormous surface area, and are known to be extremely strong.
Source: You Tube, MIT
The team created a variety of 3D models and then subjected them to various tests. The new configurations were created in the lab using a high-resolution multi-material 3D printer. The results showed that it might be possible to make 3D graphene structures so lightweight that they could even be lighter than air and could even be used as a durable replacement for helium in balloons!
However, the current research shows that at such low densities, the material may not have sufficient strength and may collapse from the surrounding air pressure.
On the other hand, there are other endless applications of this material. Different industries can take advantage of this extreme strength and lightweight. According to Buelher, “You could either use the real graphene material or use the geometry we discovered with other materials, like polymers or metals. You can replace the material itself with anything,”
“The geometry is the dominant factor. It’s something that has the potential to transfer to many things.”
The geometry the researchers used could also be applied to large-scale structural materials. Like concrete for a structure such as a bridge could be made using this geometry, as it gives comparable strength with fraction of the weight. This approach will also have the benefit of providing good insulation because of the large amount of enclosed airspace within it.
Another application is filtration systems. Since the shape has very tiny pore spaces, the material is suitable for filtration systems for either water or chemical processing.