7 Things You Might Not Know About HEAs

Researchers from Harvey Mudd and the University of New South Wales (UNSW) in Australia continue to advance strategies for developing novel high-entropy alloys (HEAs) with properties exceeding those of conventional engineering metals. Thanks to support from a three-year, $229,898 National Science Foundation grant, this work will continue. Lori Bassman, professor of engineering, associate dean for academic affairs and principal investigator for the project, has collaborated with researchers from UNSW since 2006 and has involved Harvey Mudd students for the past eight summers.

Lori Bassman, professor of engineering, associate dean for academic affairs and principal investigator for the project
Lillian Liang ’18, Kate Reed ’18 and Adam Shaw ’18 work on high-entropy alloy research at the University of New South Wales in Sydney, Australia.

Here are some impressive facts about this research:

  1. HEAs are the focus of considerable attention due to their potential to exceed traditional alloys in a broad range of important uses, from their incorporation in lightweight, high-strength structures to their use in hightemperature and corrosive environments.
  2. Traditional alloys used in engineering applications, including steel and aluminum, are formed using a primary solvent element combined with small quantities of other elements. HEAs consist of at least four elemental components containing substantial content of each.
  3. Students will fabricate, characterize and model HEAs. Among the project goals is the development of key thermodynamic and electronic principles that predict formation of ductile intermetallic phases and the atomic ordering and disordering of those phases.
  4. Results of this work could potentially include several new alloy systems plus an experimentally validated strategy that will enable efficient development of further novel HEA systems.
  5. Over the next three summers, five Harvey Mudd students funded by the NSF grant and the Jude and Eileen Laspa Fellowship in Applied Mechanics will work at UNSW’s School of Materials Science and Engineering and Electron Microscope Unit and also will complete at least two academic semesters of complementary research at Harvey Mudd.
  6. Students have an opportunity to work with UNSW specialists, including Kevin Laws, a leading expert in compositionally complex metal alloys, and Karen Privat, an expert on quantitative electron beam microanalysis.
  7. Research by Harvey Mudd and UNSW participants has yielded patent filings for two new families of HEAs as well as eight published journal articles, nine refereed conference papers and five poster presentations.
Shaw prepares a sample.