Microstructural characterization and thermal stability of AlCrFeNiTi + Y2O3 high-entropy alloy nanocomposites prepared by mechanical alloying

•Nano composites with AlCrFeNiTi HEA matrix and Y2O3 reinforcement were synthesized.•The nano composite is nanocrystalline with an average grain size of 39 nm.•HEAnC-3 powder showed stability up to 1000 °C in DSC analysis. The study focuses on the development of lightweight nanocomposites using a powder metallurgy route. Y2O3 nanoparticles (1, 2, and 3 wt%) are added to an AlCrFeNiTi high-entropy alloy (HEA) matrix. The addition of Y2O3 nanoparticles leads to the formation of a small intermetallic phase in HEA matrix. With increasing Y2O3 wt.%, the size of the crystallites diminishes starting from 32.7 nm (HEA) to 10.3 nm (HEAnC-3). TEM examination reveals that the alloy is nanocrystalline with an average grain size of 39.2 ± 2.1 nm. DSC study indicates that the nanocomposites are stable up to 1000 °C, making them ideal for high-temperature applications.