Tough alloy tested at 1112°F to replace steel in nuclear reactors

Researchers at Canadian Nuclear Laboratories (CNL) are investigating high entropy alloys (HEAs) as potential replacements for stainless steel in nuclear reactors, aiming to improve materials that withstand extreme heat and radiation. HEAs differ from conventional alloys by combining five or more metals in roughly equal atomic proportions, resulting in a stable solid solution with a distorted lattice structure that imparts unique properties such as high strength, ductility, corrosion resistance, and radiation tolerance. The study focused on an HEA composed of iron, manganese, chromium, and nickel, chosen for its stability at high temperatures and manufacturability. Using the ultrabright synchrotron light at the Canadian Light Source, the team exposed the HEA to high-energy protons at 752°F (400°C) and 1112°F (600°C) under varying radiation doses. They observed the formation of small defects called Frank Loops, which increased with temperature, and noted elemental segregation within the alloy at higher temperatures. While the HEA demonstrated better