ADVANCED MATERIALS & PROCESSES | OCTOBER 2024 10 PROCESS TECHNOLOGY ADVANCED ALLOY ATOM ARRANGEMENT A group of researchers from Penn State University, University Park, Pa., uncovered new findings about how atoms arrange themselves to find their preferred neighbors in multi-principal element alloys (MPEAs). The scientists say their discovery could enable engineers to customize these unique and useful materials for enhanced performance in specific applications ranging from advanced power plants to aerospace technologies. One of the major gaps in understanding MPEAs has been the formation tory in Iowa developed a new recycling process that eliminates the need for chemicals and high heat. The battery recycling and water splitting (BRAWS) technology uses only water and carbon dioxide to complete the process. It doesn’t require chemicals or heat and allows scientists to recover more lithium from spent batteries than other recycling methods. When lithium-ion batteries undergo fast charging, they don’t last as long because the fast charging causes the lithium to build up on the anode. Over time, the lithium build-up causes the battery to fail. The first step in the BRAWS technology is to use a set of protocols that includes fast charging to force as much additional lithium as possible to build up on the battery anode. After the battery is dismantled, the anode—typically made of graphite— is then immersed in water, and CO2 is added to recover lithium as lithium carbonate. This step results in recovery of almost all the lithium from the original battery and produces green hydrogen as a byproduct. And since the technology doesn’t rely on chemicals or extreme temperatures, other materials can be extracted in a form that can be directly reused. The scientists say their recycling process is sustainable not only environmentally but economically as well. ameslab.gov. and control of short-range order (SRO), which refers to a non-random arrangement of atoms over short distances— typically only a few atoms wide. The researchers discovered that SRO is an inherent characteristic in MPEAs, forming during the solidification process when fabricating such materials, which involves the liquid components hardening. Instead of being completely random, SRO features atoms clustering in a specific order. This clustering can affect MPEA properties, such as strength or conductivity. The researchers’ findings challenge the previous notion that, if the cooling rate during solidification is rapid, elements in MPEAs randomly arrange themselves in the crystal lattice. It also confronts the idea that SRO primarily develops during annealing, where heating and gradual cooling enhance the material’s microstructure to improve properties like strength, hardness, and ductility. The team used an improved semi-quantitative electron microscopy method to study SRO in cobalt/chromium/nickel-based MPEAs. They were surprised to find that SRO forms during the solidification process, regardless of cooling rates or thermal treatments applied. Understanding that SRO is inherent and forms during solidification means that traditional methods of thermal processing methods may not effectively control it. The researchers also discovered that the pervasive nature of SRO enabled them to tune MPEAs for particular properties, opening new possibilities for material design and engineering. psu.edu. RECYCLING LITHIUM-ION BATTERIES WITHOUT HEAT OR CHEMICALS A team of scientists from the DOE’s Ames National LaboraHeidelberg Materials North America, Irving, Texas, converted its Speed, Indiana, cement plant to a slag grinding facility to support increased demand for more sustainable cementitious products in the Midwest market. heidelbergmaterials.us. BRIEF The cloud blocking the view in this illustration indicates that the transformation mechanism from liquid metal to a high-entropy alloy solid is unclear. Courtesy of Yang Yang/Ying Han. Materials extracted using the BRAWS technology. Courtesy of Ames National Laboratory.
RkJQdWJsaXNoZXIy MTYyMzk3NQ==