Collaborative Research: RUI: IRES - Track I: US-Australia collaboration on a new class of lead-free copper alloys to meet international health demands

U.S. undergraduate students from Harvey Mudd College (HMC) and University of California (UC) Merced will collaborate with researchers at University of New South Wales, Sydney, Australia to develop a new class of non-toxic, commercially viable, brass-type alloys. Due to the severe health impacts of environmental lead, legislation to eliminate it from infrastructure and products is rapidly being implemented, with particular focus on the lead-containing brass alloys used in municipal and residential plumbing.

The alloys developed through this project will be a critical contribution toward meeting the global challenge of eliminating lead-containing brasses within the next decade. The project will provide international research mentoring for a diverse group of undergraduates (15 total over three years), including engineering, chemistry, and physics majors at HMC and UC Merced.

Students underrepresented in science and engineering, and especially first-generation college students, will be encouraged to take advantage of this opportunity. In the School of Materials Science and Engineering and the Electron Microscope Unit at UNSW, the students will have extensive access to laboratories, microscope facilities, training, and physical metallurgy expertise.

This project will contribute to the maturation of students into confident, enthusiastic researchers who are prepared for science and engineering careers in international research environments.

Current alternatives for leaded brass have manufacturing, material property and cost limitations. This project will utilize the performance/cost benefits and flexibility of a compositionally-complex brass alloy system developed previously through IRES-supported collaboration with UNSW researchers as the base for a new family of alloys that will fill the materials gap left by the exit of leaded brasses.

With the guidance of their UNSW mentors, students will develop the proposed alloys by incorporating new cost-effective, non-toxic candidates to perform the lubricating and chip breaking functions of lead during machining. They will conduct experimental and computational projects to investigate key mechanisms responsible for desirable mechanical properties and workability, and to optimize the alloy family for these properties and machinability.

These projects will engage students in thermodynamic modeling, first principles atomic-scale computational modeling, experimental alloy fabrication, and mechanical and microstructural characterization. The goal is for the proposed alloy family to provide a commercially viable replacement for leaded brasses to meet emerging legislation aimed at major health and environmental benefits.

This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.