February AMP_Digital

A D V A N C E D M A T E R I A L S & P R O C E S S E S | F E B R U A R Y / M A R C H 2 0 1 9 1 2 NOVEL PLASTIC SUITS HIGH-TEMP ELECTRONICS Researchers at Purdue University, West Lafayette, Ind., created a unique plastic material made of two organic sources to make electronics that can withstand extreme heat. The new plas- tic could reliably conduct electricity at up to 220°C (428°F), whereas most com- mercial electronics operate between −40° and 85°C. Beyond this range, these devices tend to malfunction. To over- come this limitation, the team created a material composed of two polymers that can operate at high temperatures. One of the components is a semi- conductor while the other is a conven- tional insulating polymer. The research- ers discovered a few properties that are essential to make this technology work for electronics—the two materials need to be compatible with mixing and should each be present in roughly the same ratio. This results in an organized, interpenetrating network that allows the electrical charge to flow evenly throughout while holding its shape in extreme temperatures. Most noteworthy about the new material is not its ability to conduct electricity in extreme temperatures, but that its performance does not seem to change within those conditions. Ex- treme-temperature electronics are crit- ical to the functioning of vehicles and airplanes, and the new plastic material could have many additional applica- tions in transistors, solar cells, and sen- sors. purdue.edu . DOUBLE DUTY MATERIAL INSULATES AND CONDUCTS Researchers from the University of Wisconsin–Madison, discovered a new method of electronic switching. The sci- entists created a material that can tran- sition from an electricity-transmitting metal to a nonconducting insulating material without changing its atomic structure. The new material could lay the groundwork for ultrafast electronic devices. The team used vanadium diox- ide, which is a metal when it is heated and an insulator at room temperature. At high temperatures, the atoms that makeupvanadiumdioxidearearranged in a rutile phase. When vanadium diox- ide cools down to become an insulator, its atoms adopt a monoclinic pattern. No naturally occurring substances con- duct electricity when their atoms are in the monoclinic conformation. Vanadium dioxide transitions be- tween a metal and an insulator at dif- From left, Mark Rzchowski and Chang- Beom Eom created a newmaterial that can be switched from electrical conductor to insulator. Courtesy of UW- Madison/SamMillion-Weaver. EMERGING TECHNOLOGY ASM International will provide data management support for the project “Machine Learning and Supercomputing to Predict Corrosion/Oxidation of High-Performance Valve Alloys,” which recently received $1.5 million in DOE funding. The project is led by Oak Ridge National Laboratory with support from Federal-Mogul Corp., Pennsylvania State University, and ASM. ornl.gov. BRIEF ferent temperatures depending upon the amount of oxygen present in the material. The team leveraged this fea- ture to create two thin layers—one with a slightly lower transition temperature than the other—sandwiched on top of each other, with a sharp interface be- tween. When they heated the thin vana- dium dioxide sandwich, one layer made the structural switch to become a metal and atoms in the other layer remained locked into the insulating monoclinic phase. Surprisingly, that part of the ma- terial conducted electricity. Although other research groups have attempted to create electrically conductive insulators, those materials lost their properties almost instantly. The UW researchers were able to stabi- lize their insulator, making it useful for practical devices. Key to their approach was the dual-layer sandwich structure. Each layer was so thin that the interface between the two dominated how the entire stack behaved. wisc.edu . A new organic plastic allows electronics to function in extreme temperatures without sacrificing performance. Courtesy of Purdue/John Underwood.