CTT-other mat stories

CTT-other mat stories

Research provides new insights into bulk metallic glasses

Featuring a non-crystalline amorphous structure, bulk metallic glasses can be as strong or even stronger than steel, as malleable as plastics, conduct electricity, and resist corrosion. But they are often brittle, with poor and uneven fatigue resistance. Researcher at Lawrence Berkeley National Laboratory and Caltech found that a bulk metallic glass based on palladium displayed fatigue strength as good as the best composite bulk metallic glasses and comparable to regular polycrystalline structural alloys. Palladium has high “bulk-to-shear” stiffness ratio that counteracts the intrinsic brittleness of glassy materials because the energy needed to form shear bands is significantly  lower than the energy required to turn these shear bands into cracks, the researchers say.

Scientists develop new, cost-effective magnetic storage materials

An international team of European and Japanese scientists led by the University of York has launched a €4.6million project to replace iridium metal commonly used in magnetic storage devices. All spin electronic devices, including hard disk drives and next-generation magnetic memories, use an increasingly costly iridium alloy. The researchers intend to develop Heusler alloy films—intermetallic ferromagnetic materials based on elements such as manganese, copper, and tin—to replace iridium-based materials for memory applications. According to the scientists, the price of iridium has quadrupled in the past five years and has increased by more than a factor of 10 in the last decade.

Chaotic physics hints at ‘brain-like computing’ in ferroelectrics

Unexpected behavior in ferroelectric materials explored by researchers at Oak Ridge National Laboratory supports a new approach to information storage and processing. Ferroelectric materials are known for their ability to spontaneously switch polarization when an electric field is applied. An ORNL-led research team discovered that, written in dense arrays, surface domains on ferroelectric materials began forming complex and unpredictable patterns on the material’s surface. After studying domain formation patterns under varying conditions, the scientists realized the complex behavior could be explained through chaos theory, and that the system possesses key characteristics needed for miscomputing, an emerging computing paradigm in which information storage and processing occur on the same physical platform, and a system analogous to how the human brain operates.

Will 2-D tin be the next ‘super material’?

A single layer of tin atoms could be the world’s first material to conduct electricity with 100% efficiency at temperatures at which computer chips operate, according to a research team led by scientists from the SLAC National Accelerator Laboratory and Stanford University. Called  “stanene,” the material possesses novel electrical properties that could increase speed and reduce power requirements for future electronic devices, if predicted properties are experimentally confirmed. Work to do that is already underway at several laboratories, a researcher says. Earlier this year, the scientists calculated that a single layer of tin would be a topological insulator at and above room temperature, and that adding fluorine atoms to the tin would extend its operating range to at least 100°C.

Copper nanowires an inexpensive potential alternative for solar energy harvesting

Converting solar energy into storable fuel remains one of the great challenges of modern chemistry. Chemists have tried to capture solar energy using catalyzed water splitting to produce hydrogen, and indium tin oxide is one material they’ve commonly tried to use. Now researchers at Duke University say copper nanowires fused in a see-through film could replace ITO as water-splitting catalysts. The copper nanowire catalysts are relatively inexpensive because they can be “printed” on glass or plastic and they provide a large surface area for catalysis, the researchers say. Even with a coating of cobalt or nickel, the nanowire films are said to allow nearly seven times more sunlight to pass through than ITO.