[TheDevs]

Scientists Develop Tool to Predict Behavior of High-Entropy Alloys in Extreme Environments

Scientists from the Department of Energy’s Pacific Northwest National Laboratory and North Carolina State University have developed a tool to predict the behavior of high-entropy alloys in extreme environments. These alloys, known as multi-principal element alloys or medium- to high-entropy alloys, are being explored for applications in nuclear fusion reactors, hypersonic flights, and high-temperature jet engines.

The research, published in the journal Nature Communications, combines atomic-scale experiments with theory to create a roadmap for designing oxidation-resistant complex metal alloys. The goal is to identify alloys with superior resistance to extreme environments, such as the aerospace and nuclear power industries.

In their recent experiments, the research team focused on a high-entropy alloy called the Cantor alloy, which consists of equal amounts of cobalt, chromium, iron, nickel, and manganese. By studying the oxide formed on the Cantor alloy, the scientists discovered that chromium and manganese migrate quickly to the surface and form stable oxides. Iron and cobalt then diffuse through these oxides to create additional layers.

To enhance the oxidation resistance of the Cantor alloy, the researchers introduced a small amount of aluminum, which acted as a barrier for other elements migrating to form the oxide. This reduced overall oxidation and increased the alloy’s resistance to degradation at high temperatures.

The team also developed a model called the Preferential Interactivity Parameter, which allows for early prediction of oxidation behavior in complex metal alloys. This model provides a deeper understanding of oxidation mechanisms across all complex alloys.

The researchers aim to expand their research to develop complex alloys with exceptional high-temperature properties. They plan to integrate additive manufacturing methods and advanced artificial intelligence to rapidly evaluate promising new alloys. This project is part of the Adaptive Tunability for Synthesis and Control via the Autonomous Learning on Edge (AT SCALE) Initiative at Pacific Northwest National Laboratory.

The ultimate goal is to select a combination of elements that favor the formation of a stable and protective oxide, capable of withstanding extreme heat in applications such as rocket engines and nuclear reactors.

The research team’s findings provide valuable insights into the mechanisms of oxidation in complex alloys at the atomic scale. This breakthrough brings us closer to designing next-generation alloys with superior resistance to extreme environments, paving the way for advancements in various industries.

The study involved collaboration between scientists from Pacific Northwest National Laboratory, North Carolina State University, Lawrence Berkeley National Laboratory, and Brookhaven National Laboratory. The research team utilized advanced atomic-scale methods, including in situ atom probe tomography, electron microscopy, and synchrotron-based X-ray scattering, to investigate the arrangement of atoms within the samples.