Space science

Researchers from Lehigh University, the U.S. Army Research Laboratory, Arizona State University, and Louisiana State University have developed a nanostructured copper alloy with exceptional thermal stability and mechanical strength, making it one of the most resilient copper-based materials ever created. The breakthrough comes from the formation of copper-lithium precipitates, stabilized by a tantalum-rich atomic bilayer complexion.

In a Perspective article published in Nature Materials, two engineers at the Massachusetts Institute of Technology, Carlos Portela and James Surjadi, discuss key hurdles, opportunities, and future applications in the field of mechanical metamaterials. Metamaterials are artificially structured materials with properties not easily found in nature. With engineered three-dimensional geometries at the micro- and nanoscale, metamaterials achieve unique mechanical and physical properties with capabilities beyond those of conventional materials.

Researchers from Columbia University; the Molecular Foundry at the U.S. Department of Energy’s Lawrence Berkeley National Laboratory; and the University of Utah have invented new nanoscale sensors of force. They are luminescent nanocrystals that can change intensity and/or color when you push or pull on them. These "all-optical" nanosensors are probed with light only and therefore allow for fully remote read-outs—no wires or connections are needed.

A nanocrystalline material is made up of many tiny crystals, but as they grow, the nanocrystalline material can weaken. Researchers from Lehigh University, Johns Hopkins University, George Mason University, the University of Tennessee, Knoxville, and the U.S. Department of Energy’s Lawrence Berkeley National Laboratory and Sandia National Laboratories have discovered that the key to maintaining the stability of nanocrystalline materials at high temperatures lies in triple junctions – corners where three of these nanocrystals meet.

Imaging the hot turbulence of aircraft propulsion systems may now be possible with sturdy sheets of composite materials that twist light beams, according to researchers from the University of Michigan, the Air Force Research Laboratory, ARCTOS Technology Solutions (Beavercreek, OH), the Brazilian Center for Research in Energy and Materials in Campinas, Brazil, and the Federal University of São Carlos in Brazil. The key is arranging nanomaterials that don't twist light on their own onto layers that turn light waves into either left- or right-handed spirals, known as circular polarizations.

Researchers from the Massachusetts Institute of Technology, Universitat de Girona in Spain, and Universidade do Porto in Portugal have shown that they can prevent cracks from spreading between layers in a composite material by depositing chemically grown forests of carbon nanotubes between the composite layers. The tiny, densely packed fibers grip and hold the layers together, like ultrastrong Velcro, preventing the layers from peeling or shearing apart.

Engineers from the Massachusetts Institute of Technology (including the MIT Institute for Soldier Nanotechnologies) and the Army Research Laboratory have developed a new way to quickly test an array of metamaterial architectures and their resilience to supersonic impacts. Metamaterials are functional materials that contain unique microscale and nanoscale patterns or structures. The engineers suspended tiny, printed metamaterial lattices between microscopic support structures and then fired even tinier particles at the materials, at supersonic speeds.

One of the most important components of satellites that enable telecommunication is the waveguide, which is a metal tube for guiding radio waves. It is also one of the heaviest payloads satellites carry into orbit. Now, researchers from Drexel University and the University of British Columbia are trying to lighten the load by creating and testing a waveguide made from 3D-printed polymers coated with a conductive nanomaterial called MXene.