By the end of 2021, employees of the Russian JSC SSC “Keldysh Center” must complete research work on the creation of a layered “self-healing” material. As RT was told in the press service of the enterprise, we are talking about a special composite that neutralizes minor damage to the surface of spacecraft. It is capable of providing intensive mass transfer to the area of a cut or puncture and, as scientists expect, will improve the security of orbiters and space suits that are exposed to cosmic dust. According to experts, on earth, the “self-healing” material will come in handy in the manufacture of containers for the storage of hazardous liquid substances.
In December 2021, the specialists of JSC SSC Keldysh Center (part of Roscosmos) will complete research work on the creation of a layered “self-healing” material. This was reported to RT in the press service of the enterprise.
“Research work on the production of composite materials with a polymer matrix based on borosiloxane compounds will be completed in December this year. The project is being carried out in cooperation with the RFBR (Russian Foundation for Basic Research), “the press service told RT.
The Keldysh Center is the head research enterprise of Roscosmos in the field of rocket propulsion and space energy. It is also determined by the head organization of the state corporation in the direction of “Functional materials for space technology.”
The composite material developed at the Keldysh Center is capable of demonstrating a quick self-healing effect (restoration of tightness) in the composition of inflatable structures with an internal atmosphere.
A composite with a polymer matrix based on borosiloxane compounds, developed by Russian scientists, has a layered structure with a combination of layers with different functional properties. This layered architecture allows mass transfer of the borosiloxane matrix to the site of damage, while the outer layers of the composite perform protective and structural functions.
Samples of the composite “self-healing” material were puncture and cut tested. Tests have shown effective “self-healing” for punctures up to a few millimeters in size.
“Borosiloxane compounds are a non-Newtonian fluid that, while flowing under static load, penetrates the pores (holes), blocks them and prevents air from escaping. To obtain additional properties, reinforcing and activating components are added to borosiloxane. For example, layers of partially crosslinked borosiloxane exhibit shape memory under elastic stretching, and the central layer of viscous borosiloxane is responsible for intensive mass transfer to the area of a cut or puncture, ”the press service of the Keldysh Center explained.
In the summer, a prototype of this product was demonstrated at the International Aviation and Space Salon (MAKS-2021) and at the Army-2021 International Military-Technical Forum.
The company’s brochure states that the fundamental architecture of a “self-healing” material is “a system of several functional layers, each of which performs a specific task, which makes it possible to achieve self-control of the entire system when a defect that is applied activates the self-healing process.”
Specialists of the Keldysh Center have created prototypes of several types of such a composite with different architectures of the inner layers and borosiloxane matrices, which differ in density, hardness, viscosity and other properties. For example, in one variation of the “self-healing” material, carbon fibers were added, which increased the hardness and reinforced the composite material.
The stand of the Keldysh Center with samples of “self-healing” material / © JSC State Research Center “Keldysh Center”
In a commentary on RT, a researcher at the enterprise, Irina Zaletova, noted that the “self-healing” material can be useful primarily for protecting transport and other spacecraft from mechanical damage that occurs after exposure to micrometeoroids and particles of small space debris.
As Zaletova said, different types of composites with a polymer matrix based on borosiloxane compounds are also appropriate to use in the construction of the ISS, in space modules under development and in materials for spacesuits.
There are a lot of spheres of practical application of “self-healing” material. However, before that, a large amount of work has to be done: it is necessary to more accurately assess the weight and size characteristics of the product and modernize the design for direct use as part of various modules of spacecraft, Zaletova emphasized.
Answering RT’s question about the product’s ability to withstand the hit of space debris with a diameter of more than 0.5 cm, Zaletova did not rule out such a possibility, but noted the need for further research and experiments.
Earlier, the general director of the Keldysh Center, Vladimir Koshlakov, said that such composite materials can be used “not only for rocket and space technology, but also in other high-tech industries.”
“We need new materials”
Experts interviewed by RT consider it extremely promising to conduct further research and testing of the “self-healing” material. In their opinion, composites with a polymer matrix based on borosiloxane compounds can find wide practical application both in orbit and on the ground.
In a commentary on RT, Nathan Eismont, a leading researcher at the Institute for Space Research (IKI RAS), said that the “self-healing” material would definitely be suitable for making more protected spacesuits. According to him, modern materials do not always reliably protect astronauts.
Cosmic dust in the Horsehead Nebula / NASA / © NOAO, ESA and The Hubble Heritage Team STScI / AURA
“It is quite expected that a composite with a polymer matrix based on borosiloxane compounds will be used to improve the protective properties of spacesuits. For expeditions to the same moon, more durable spacesuits are required. After all, it is assumed that astronauts will work there, chipping off pieces of asteroids, ”said Eismont.
Senior Researcher at the Institute of Astronomy of the Russian Academy of Sciences, Candidate of Physical and Mathematical Sciences Sergei Naroenkov believes that, first of all, “self-healing” material will be required to protect spacecraft. In an interview with RT, he noted that the composite created by the Keldysh Center should become a barrier against the effects of cosmic dust (micrometeorites).
Cosmic dust is particles of solid matter ranging in size from a few molecules to tens of microns, located in outer space. In recent studies, it has been argued that it arises mainly from comets.
In 2017, the scientific journal Physics of Plasmas published an article by scientists from Boston University on the threat posed by cosmic dust. As reported in the material, getting into the equipment of satellites and probes, micrometeorites form plasma mini-clouds, in the center of which powerful electromagnetic waves arise. As a result, various malfunctions of the electronic filling suddenly occur. Under certain circumstances, violations can lead to an accident and the loss of a spacecraft. In particular, it was the effect of cosmic particles (cosmic rays) that was recognized as the main cause of the accident at the Russian interplanetary station Phobos-Grunt on November 9, 2011.
“The devices can really fail when space particles penetrate. The problem of effective protection of satellites and other devices has not gone off the agenda, ”Naroyenkov stressed.
According to the scientist, special screens and coatings are used to protect orbiters from cosmic dust attacks, but they can be severely damaged. According to Naroenkov, the materials used allow particles of a certain size and dust elements to pass through, which fly at high speeds.
“New materials are needed to contain space dust, so a composite with a self-tightening effect can certainly be called a promising development,” explains the interlocutor of RT.
According to the expert, on earth, a material with a polymer matrix based on borosiloxane compounds can be used to protect surfaces from damage caused by land dust, as well as in the manufacture of containers for storing hazardous liquid substances.
Cover photo: Satellites in orbit / Reuters / © Oleg Novitskiy / Roscosmos / Handout