LLNL researchers, working closely with partners at Oak Ridge National Laboratory, Ames Laboratory and Eck Industries, have discovered a new family of aluminum alloys that offers superior mechanical properties over standard aluminum at high temperatures. The new alloy has the potential to lower manufacturing costs compared with most other standard alloys, while also creating a new market for the rare earth metal cerium.

First developed as a project within the Critical Materials Institute (CMI), a Department of Energy Innovation Hub, the motivation for the work was to find a demand for cerium, which is overproduced and generally redeposited back into mines as a part of regular mining operations. Creating a demand for cerium, which typically constitutes about 50 percent of the rare earth content, may sharply improve the economic viability of rare earth mining.

When combined with aluminum, researchers found the Aluminum/Cerium (ACE) alloy performed roughly two-to-three times better than standard aluminum alloys at higher temperatures, showed excellent castability, had higher corrosion resistance than standard aluminum, and perhaps most importantly, eliminated the need for heat treatment after casting, which could reduce manufacturing costs by up to 60 percent, saving energy and time.

The discovery could change mining economics and has the potential to transform how mines operate if the demand for the material goes up. It also could prove useful in making lightweight engines for light planes, automobiles and motorcycles, as well as for associated engine components such as turbochargers. It has been deployed for impeller blades in small-scale hydroelectric generators, as well as pistons for high-performance gasoline and diesel engines.

Credit: Lawrence Livermore National Laboratory