Prototyping new or improved specialty metal alloys, to determine whether they'll perform as required in industrial settings, is fraught with uncertainty. Can the material devised in a laboratory be manufactured in industrial-scale quantities and still have the properties to perform as expected in the real world?
The Advanced Alloys Signature Center (AASC), an initiative of the National Energy Technology Laboratory (NETL), was formed recently to help accelerate commercialization of new alloys by bridging the gap between small, research-scale quantities and large-scale industrial needs.
At universities, private companies, and government labs, researchers working on new specialty alloys make very small amounts of materials to assess properties and validate concepts. They're also typically produced using techniques and methods that aren't "industrial relevant," and those alloy concepts can't be readily translated to industry, said David Alman, NETL's associate director, materials engineering and manufacturing.
"Many research organizations can prototype new alloys on a scale of 10 pounds or less," he said. "Meanwhile, most commercial concerns need alloy ingots on the order of thousands of pounds or more. In the laboratory, you may come up with a material that has great properties, but can you manufacture it in real life? That's what the AASC tries to address."
It's About Processes as Well as Materials
The AASC can prototype alloys at ingot sizes up to 500 pounds, enough material for a full-scale evaluation of a composition's materials concepts so its properties will translate to commercial practice, said Alman.
Quantity is only one part of the story. The AASC leverages science-based models, artificial intelligence and machine learning, data analytics, and high-performance computing to help accelerate technology development, using specialized tooling and processes. It also has a full suite of testbeds to closely simulate in-service environments.
The AASC doesn't claim the material will have the required properties until it's upscaled, and industrial-relevant processes are used, said Alman.
Although NETL is a U.S. Department of Energy national laboratory, applications for the alloys evaluated at the AASC are much broader than energy. "In the work we do with traditional cast, forged, or rolled material we focus on high-temperature, heat-resistant alloys for energy applications," said Alman. "But we also produce nickel-based superalloys used in very high-temperature applications like jet engines and turbines."
NETL has used the AASC's capabilities for its own research and to assist other national laboratories, the Department of Defense, universities, and companies in automotive, bio-medical, and other fields to upscale new alloys, he said.
While the alloy development capability has existed for many years at NETL, it was refreshed and expanded to form the AASC in 2020, and more formally unveiled last November with the publication of a fact sheet.
Up Next: New Types of Metal Alloys
The AASC focuses on mission-critical applications. "If you have a material for, say, a large land-based gas turbine, the components are typically large, and they can't fail," said Alman.
For these, industry typically produces ingots through a triple melt process to eliminate impurities in materials that can lead to failure. While it's unusual to have capabilities in all three—vacuum induction melting (VIM), vacuum arc remelting (VAR), and electro-slag remelting (ESR)—at one research location, the AASC does.
NETL Research engineer Martin Detrois programs a heat-treating furnace. The furnace is a smaller version of the one commonly used by industry to heat-treat nickel base superalloy components for aerospace applications.
The AASC typically works with steel and nickel superalloys and is developing some alloys that are corrosion resistant and hydrogen resistant and have high-temperature capabilities. It's made one of the largest ingots in the world, at 150 pounds, of a high-entropy alloy, an emerging new class, said Alman.
The AASC uses science and its computational design approach to lead development. "NETL's resources include our JOULE 2.0 supercomputer and our Center for Artificial Intelligence and Machine Learning to optimize processes and alloys to come up with some unique alloys," he said. It is also moving into custom feedstocks for additive manufacturing, especially newer solid state processes that use solid material, instead of the more typical powder and wire processes.