By studying the behavior of complex fluids in microgravity, researchers have paved the way for new, cutting-edge manufacturing processes that could benefit many industries.
There Microgravity Staying on board the International Space Station opens the door to many fascinating works. By studying the behavior of matter that has escaped the clutches of gravity, researchers can isolate many phenomena that help them understand how our world works.
These experiments have already produced great results in a wide variety of fields, from cell biology to fluid mechanics to materials science. The Scottish University of Strathclyde in Glasgow has recently stood out in this context. Thanks to an experiment carried out on board the ISS, a team of researchers has achieved this produce new materials that can soon be tested on Earth.
Complex liquids, fascinating substances
This experience started with the work complex liquids. These are substances in which two phases of matter (solid, gaseous or liquid) coexist. These can be, for example, liquids that contain a large number of solid particles; the complex liquid is then called a suspension. It can also contain tiny droplets of another liquid, which is then called an emulsion, or a significant amount of gas (it is then a foam).
The term complex fluid is used to mark the difference from so-called simple or Newtonian fluids. The latter have a uniform and constant viscosity; So they spill in predictable ways.
The flow of complex liquids, on the other hand, can vary depending on many parameters. You can easily make an example of this in your kitchen. When you mix water and cornstarch, you get a liquid that you can easily dip your hand into. On the other hand, the more this mixture is subjected to significant force, the more viscous it becomes until it becomes almost completely solid. So you could walk on it at full speed without sinking.
This is just an isolated example; the various complex liquids can be present many other fascinating features. These peculiarities are the basis of a very active area of research because these substances are ubiquitous in the world around us. They are straight vital; vital; Blood is a good example of a complex fluidsince it consists of particles (spheres, platelets, etc.) suspended in a liquid phase.
A completely new way to produce advanced materials
They have many specific applications, especially in the food industry, the cosmetics industry or biology. For their part, Marcello Lappa’s team explored their interest Materials Science. Based on sophisticated computer simulations, the researchers postulated that it should be possible to produce new materials from complex fluids in weightlessness.
So they tried to test this theory by sending an experiment called T-PAOLA aboard the International Space Station. Once on site, the resident astronauts performed various protocols that involved heating and then vibrating various types of complex liquids.
Astronaut Frank Rubio installs the experimental equipment on board the ISS. © T-PAOLA 
© T-PAOLA
And apparently they have achieved very promising results. “We showed that by shaking a complex liquid without gravity, particles can do incredible things,” says Lappa. “Instead of moving randomly, they can form clusters and even perfect networks whose properties can be controlled with great precision.” »
Towards the era of space manufacturing
The team has not yet published the associated study. It is therefore currently impossible to know exactly what type of material this is. But this process could still be of significant importance in our time, when industry is increasingly interested in orbital manufacturing.
The world’s first space factory is now in orbit
“Manufacturing in space takes advantage of the characteristics of this environment to produce materials of much higher quality than on Earth, and we could use it to improve mountains of materials that are critical to our health and our industry,” the university press release said . This could even lead to the creation of completely new materials whose properties simply could not be reproduced on Earth.
“These could include metal alloys that are characterized by an internal structure that can withstand very specific stresses, non-metallic materials that can conduct electricity, or even crystalline proteins for the pharmaceutical industry.”
From now on, Lappa’s team will try to make this method accessible to industry and research institutions. It will therefore be very interesting to follow the impact of this work, which could lead to the first examples of large-scale space manufacturing.