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 | A P R I L 2 0 2 3 6 METALS | POLYMERS | CERAMICS Scientists at the University of Bristol, U.K., discovered a chromium-cobalt-nickel alloy that exhibits increased strength at temperatures as cold as -250°C, making it the toughest material on record. The alloy’s behavior is due to a phase transformation that combines with other nanoscale mechanisms to prevent crack formation and propagation. www.bristol.ac.uk. Set to debut this fall, Colorado School of Mines will offer a bachelor of science in ceramic engineering. In the U.S., only two other such programs exist, one at Alfred University in New York and another at Missouri University of Science & Technology. Students will receive hands-on training in ceramic processing, sintering, glass science, and thermal, mechanical, and electrical properties. mines.edu. BRIEFS on single crystals over the last three decades, but growing the crystals with melt processing and controlling their orientations has been quite challenging,” explains Karaman. “The method Hande discovered now saves us a lot of time and provides more flexibility.” Controlling the size, shape, and crystallographic orientation of single crystals is vital to exploit the desired properties, the researchers say. Single crystals are essential to microelectronics, optical crystals, magnetic devices, solar cells, piezoelectric components, and multifunctional alloys. Another advantage to their new technique, according to the researchers, is that it does not require complex and expensive equipment. The newmethod is called the solid-state crystal growth (SSCG) technique, where large bulk crystals with different crystallographic orientations could be made with simple heat treatments. The Texas A&M research team demonstrated the SSCG method in two alloy systems—FeMnAlNi CARBON-REDUCING SUPERALLOY In a collaborative effort between Sandia National Laboratory, Iowa State University, Ames National Laboratory, and Bruker Corp., Billerica, Mass., scientists used a 3D printer to create a superalloy that could help power plants generate more electricity while producing less carbon The superalloy has an unusual composition that makes it stronger and lighter than state-of-the-art materials currently used in gas turbine machinery. The findings could have broad impacts across the energy sector as well as the aerospace and automotive industries, and hints at a new class of similar alloys waiting to be discovered. Sandia’s experiments showed that the new superalloy—42% aluminum, 25% titanium, 13% niobium, 8% zirconium, 8% molybdenum, and 4% tantalum— was stronger at 800°C than many other high-performance alloys and still stronger when it was brought back down to room temperature. The team at Sandia used a 3D printer to quickly melt together powdered metals and then immediately print a sample of it. Sandia’s creation also represents a fundamental shift in alloy development because no single metal makes up more than half the material. By comparison, steel is about 98% iron combined with carbon, among other elements. Moving forward, the team is interested in exploring whether advanced computer modeling techniques could help researchers discover more members of what could be a new class of high-performance, additive manufacturing-forward superalloys. sandia.gov, iastate.edu, bruker.com. CRYSTAL GROWTH TRANSFORMS MATERIALS Researchers at Texas A&M University, College Station, discovered a new crystal growth and orientation control method in solid-state—without melt processing. Materials scientists Hande Ozcan and IbrahimKaraman, FASM, led the research, which focused on growing large single crystals and their ability to change crystallographic orientation. “We have been working Sandia technologist Levi Van Bastian works to print material on the laser engineered net shaping machine, used for 3D printing superalloys. Courtesy of Craig Fritz. Hande Ozcan working with an x-ray machine. Courtesy of Texas A&M Engineering.
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