Cerium is a rare earth element that makes up 0.0046% of the weight of the Earth’s crust. It is used in a variety of industrial applications. It can also be used as a fuel additive in gasoline engines to improve performance and decrease emissions.
The use of cerium is growing due to the emergence of the aluminum alloy industry. As a result, cerium production is increasing to meet the market demand for aluminum alloys.
In addition, the development of new alloys that can withstand high temperatures requires research to understand their atomic-level behavior. ORNL scientists have developed a technique that maps the atom-level changes inside an aluminum-cerium alloy engine block using neutron scattering.
This study describes how the new alloy behaves under high temperatures and pressures within an operating internal combustion engine, allowing researchers to visualize changes at the atomic level in real time. The alloy has a higher melting point than aluminum alone and is more resistant to high temperature corrosion.
Unlike most other aluminum-cerium alloys, the system exhibits a unique intermetallic microstructure that traps the ceria and allows it to resist traditional coarsening interactions. It also has an exceptionally low sintering rate and high strength retention at high temperatures.
The work also provides a framework for developing new aluminum-cerium alloys, which could be a significant step toward integrating this material into the aluminum industry. The alloys provide a number of promising properties, including high heat tolerance and low coefficients of thermal expansion.