BB.lv: Scientists have created a strange meta-fluid: its properties can be programmed

Scientists from Harvard University, USA, have created a new unusual meta-fluid. It is a liquid whose properties can be programmed to change. This refers to the material’s compressibility, transparency and viscosity, writes New Atlas.

Most materials derive their properties from created structures that are made up of small components. The shape, size, and arrangement of these components allow them to manipulate electromagnetic waves to improve things like soundproofing, electricity generators, or even invisibility cloaks. Scientists who published their research in the journal Nature decided to apply this principle to liquids.

According to scientists, unlike solid metamaterials, metafluids have a unique ability to flow and adapt to the shape of the container in which they are located. Therefore, scientists wanted to create a metafluid that would have these properties, as well as be able to program its viscosity, compressibility and optical properties.

In this case, the small components of the metafluid are air-filled elastomeric spheres, 50 to 500 microns wide, that are contained in silicone oil. These tiny spheres change under pressure and return to their shape when the pressure is removed. Two different states change the properties of the metafluid.

When the spheres are round, they scatter light, causing the liquid to appear opaque. But under pressure, when they take on a crescent shape, they act like tiny lenses, focusing light and making the meta-fluid transparent. This means they might be useful as color-changing electronic ink, the scientists say.

The scientists also used metafluid as a hydraulic medium in a robotic gripper. Since the meta-fluid can automatically respond to different pressures, it adjusts its gripping force, allowing it to grasp different objects without damaging them. Typically, a hydraulic system that operates on water or air requires sensors or external controls to adjust the grip force based on the object being lifted.

According to the study authors, the new metafluid can also switch between Newtonian and non-Newtonian fluids. When the spheres are round, they are Newtonian, meaning their viscosity changes only with temperature, and they are like water, but when they are compressed, they become non-Newtonian, meaning they change viscosity and are more like tomato sauce.

Scientists believe that such meta-fluids might have different applications. In addition to the above examples, it is also possible to create shock absorbers that dissipate energy depending on the intensity of the impact.

Now scientists plan to study the acoustic and thermodynamic properties of the metafluid.