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Suppressing Atomic Diffusion with the Schwarz Crystal Structure in Supersaturated Al–Mg Alloys

Because of the nature of interatomic bonding, atomic diffusivity is notably higher in metals relative to that in ceramics and compounds with covalent or ionic bonds. This feature enables substantial tuneability of structures at various length scales by tailoring the diffusion controlled processes during the synthesis and subsequent treatments, resulting in a broad spectrum of properties and performance in metallic materials, but this causes their customized properties to be unstable at elevated temperatures.

Gradient-cell-structured High-entropy Alloy with Exceptional Strength and Ductility

In past decades, the emerging multi-principal-element high-entropy alloys (HEAs) with a near-infinite multicomponent phase space have received the growing attention of the materials community due to their unprecedented mechanical properties, such as good ductility, and exceptional damage tolerance at low temperature. However, most multicomponent HEAs lose ductility with increasing strength, owing to the similar full dislocation mediated plastic deformation in conventional materials. Still, the extraordinary low-hanging fruits that the HEA field may offer, such as novel deformation mechanism, as expected, are not seen yet.

Research on Joining of Dissimilar Materials in Massive Scientific Facility

In magnetic confinement nuclear fusion, a strong magnetic field is used as "magnetic container" to confine high-temperature plasma which is then heated to hundreds of millions of degrees to maintain continuous thermonuclear reactions. Because the fusion reactors are made of a wide variety of materials, the need to join dissimilar materials is apparently prevalent. Furthermore, all the joints are always subject to higher heat loads and serious plasma sputtering erosion. Accordingly, the joint reliability is of intense importance. However, joining of dissimilar materials with huge differences in composition, physical and chemical properties has always been the biggest bottleneck restricting their engineering applications.

Discovery of Segmented Fermi Surface in a Superconductor

Superconductivity is a long-standing research topic in physics. Superconductors have critical applications because of their unique properties like zero resistance and complete diamagnetism. When a superconductor is in the superconducting state, an energy gap will form at the Fermi level, so there is no Fermi surface in a superconductor. In 1965, theoretical physicists predicted that when the Cooper pair momentum in a superconductor is large enough, quasiparticles will be generated in the superconducting energy gap, thus forming a segmented Fermi surface. However, this prediction has not been confirmed experimentally for more than 50 years because when the Cooper pair momentum of conventional superconductors is large enough to create quasiparticles, the Cooper pair itself will break up and lose superconductivity.