September_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 | S E P T E M B E R 2 0 1 9 1 5 PROCESS TECHNOLOGY MAKING CHEAPER HIGH- PERFORMANCE ALLOYS Researchers from the Pacific Northwest National Laboratory, Rich- land, Wash., recently produced nano- structured rods and tubes directly from high-performance aluminumalloy pow- der in a single step. The advanced man- ufacturing process uses PNNL’s propri- etary Shear Assisted Processing and Ex- trusion technology, or ShAPE. The novel solid phase processing approach eliminates several steps re- quired during conventional extrusion processing of aluminum alloy powders while also achieving a significant in- crease in product ductility. The team’s development is advantageous for sec- tors such as the automotive industry. In the ShAPE process, a powder— in this case, an Al-12.4 aluminum alloy powder provided by SCM Metal Prod- ucts Inc., a division of Kymera Interna- tional, Orangeburg, S.C.—is poured into an open container. A rotating extrusion die is then forced into the powder, which generates heat at the interface between the powder and die. The material soft- ens and easily extrudes, eliminating the need for canning, degassing, hot press- ing, pre-heating, and decanning. “The elimination of both the pro- cessing steps and the need for pre-heat- ing could dramatically reduce produc- tion time as well as lower the cost and overall embedded energy within the product, which could be beneficial for automotive manufacturers who want to make passenger vehicles more af- fordable, lighter, and fuel-efficient for the consumer,” says PNNL scientist Scott Whalen. Besides providing the Al-12.4TM powder, SCM Metals Products Inc. per- formed mechanical testing to validate the resulting material’s performance. PNNL and SCM are now collaborating on a project for DOE’s Office of Technol- ogy Transitions to scale up the process for larger diameter extrusions. While high-performance alumi- num alloys have historically shown ex- cellent strength, they have typically been hampered by poor ductility. How- ever, the team found dramatic improve- ments in the ductility of the extrusion produced by ShAPE, measuring ductil- ity that is two to three times that found in conventional extrusion products, and with equivalent strength. ShAPE is part of PNNL’s growing suite of capabilities in solid phase pro- cessing—or SPP, a disruptive approach to metals manufacturing that can be better, cheaper, and greener than melt-based methods typically associ- ated with metals manufacturing. pnnl. gov. CARBON TRANSFORMS 2D SEMICONDUCTING MATERIAL Researchers from Penn State, State College, Pa., have developed a new method to alter the electronic properties of the semiconducting ma- terial tungsten disulfide. The technique introduces carbon-hydrogen molecules into a single atomic layer of the materi- al, dramatically changing its conductive potential. The new transformative process will have applications in various types of transistors. Laptops, for example, contain around 100 trillion transistors. According to the scientists, once the semiconductive material is highly doped with carbon, they can produce a degenerate p-type with a very high car- rier mobility. The researchers say they can create new varieties of components for energy-efficient photoelectric devic- es and electronic circuits with this ma- terial. psu.edu . High-strength, high-ductility rods were produced using PNNL’s ShAPE process and a unique aluminum alloy. Courtesy of PNNL/Andrea Starr. BRIEF Metal additive manufacturer Sciaky Inc., Chicago, has initiated a new research and development program in collaboration with Aubert & Duval and Airbus, France. Also known as the Metallic Advanced Materials for Aeronautics (MAMA) project, the initiative’s goal is to couple traditional metallurgy with emerging wire-fed metal 3D printing techniques to develop new processes for manufacturing titanium aircraft parts. sciaky.com. Depiction of carbon doping in a WS2 lattice. Courtesy of Penn State/Fu Zhang.