A team of scientists from nine government, academic and industrial institutions discovered that many types of glass have a similar atomic structure and can be successfully produced in space. A space glass bead is shown in the picture. Credit: Phoenix Pleasant/ORNL, US Department of Energy
Researchers have developed techniques to make different types of glass in space, revealing the potential for advances in optical technology.
Thanks to human ingenuity and weightlessness, we are reaping the important benefits of space science. Think smartphones with built-in navigation systems and cameras.
Such transformational technologies seem to be integrated into the rhythm of our daily lives overnight. But they are born out of years of discovery and development of materials that can withstand harsh conditions outside of our atmosphere. They stem from decades of foundational science to understand how atoms behave in different materials and under different conditions.
A breakthrough in materials science
Building on this past, a global team of researchers has set new standards for future experiments in materials production. IN space than For room. The team included members from the Department of Energy’s Oak Ridge and Argonne National Laboratories, Materials Development, Inc. OURJapan Aerospace Exploration Agency, or JAXA, ISIS Neutron and Muon Source, Alfred University and the University of New Mexico. Together, they discovered that many types of glass, including those that could be developed for next-generation optical devices, have similar structures and atomic arrangements and can be successfully produced in space.
“The idea is to test the mechanisms behind space production, which can lead to materials not necessarily available on Earth,” said Jörg Neuefeind, who joined ORNL in 2004 to build an instrument called NOMAD for the laboratory’s spallation neutron source. , that is, SNS. NOMAD, the world’s fastest neutron diffractometer, helps scientists measure the arrangement of atoms by watching how neutrons bounce off them. NOMAD is one of 20 SNS instruments that help scientists answer big questions and drive countless innovations, such as drugs that treat diseases more effectively, more reliable airplane and rocket engines, more fuel-efficient cars, and safer batteries that charge faster and last longer.
Advances in Space Manufacturing
JAXA operators on Earth made and melted the glass on the International Space Station (ISS), via remote control using a levitator. Levitation is used to suspend material samples during experiments to avoid interference from contact with other materials.
After the next ISS mission ended a few months later and the space glass was returned to Earth, the researchers used a combination of techniques including neutrons, X-rays and powerful microscopes to measure and compare the glass produced and melted in the sky compared to that on Earth.
“We found that with containerless techniques such as a levitator, we can create unconventional glasses in microgravity,” said JAXA’s Takehiko Ishikawa, who pioneered the electrostatic levitator used to make glass beads on the ISS.
The researchers relied on NOMAD at SNS to study the glass samples with neutrons and on the beams of the Argonne Advanced Photon Source to study the samples with X-rays.
“There’s only so much material you can fly to space and back, and that’s actually one of the reasons NOMAD is so well-suited for this experiment,” said Stephen Wilke of Materials Development Inc. and visiting scientist at Argonne. . “We only collected glass beads about an eighth of an inch in diameter, which are very difficult to measure in terms of atomic structure. Because NOMAD excels at measuring extremely small samples, it allowed us to easily compare the unique beads we made in the lab with those made on the space station.
Discovering the mysteries of glass
It turns out that glass is not so transparent. Unlike crystalline solids such as salt, glass atoms do not have a uniform structure. Its unusual atomic arrangement, although remarkably stable, is perhaps best described as a random network of molecules sharing coordinated atoms. Neither fully solid nor fully liquid, glass also comes in a variety of forms, including polymer, oxide, and metallic, such as eyeglass lenses, optical fiber strands, and hardware for deep space missions.
In 2022, Neuefeind, Wilke and Rick Weber, an expert in the glass industry, experimented with two oxides of neodymium and titanium and discovered the potential for optical applications. The combination of these two elements presents unusual advantages that are not found in similar search campaigns. These discoveries led them to continue their current studies with NASA.
“(The 2022 experiment) taught us something really remarkable,” Materials Development Inc.’s Weber said. “One of the glasses has a completely different lattice than the normal four-coordinate lattice typical of silicon. These glasses have an array of six coordinates. They are really there. This is exciting from a glass science perspective. But from a practical point of view, it also means more opportunities to create new things with optical materials and new types of devices. »
Scientists often use neutrons and X-rays in parallel to collect data that no other technique can produce, allowing us to understand the arrangement of atoms of different elements within a sample. Neutrons helped the team see lighter elements in space glass, like oxygen, while X-rays helped them see heavier elements, like neodymium and titanium. If there were significant differences between space and terrestrial glass, they would likely manifest in the oxide sublattice, or in the arrangement of oxygen atoms, in the distribution of heavy atoms, or both.
Conclusion
Neutrons will become increasingly important tools for unlocking the mysteries of matter as scientists explore new frontiers, despite space.
“We need to understand not only the effects of space on matter, but also its effects on the way things are made,” Neuefeind said. “Because of their unique properties, neutrons help solve these kinds of puzzles. »