Effect of Ti on the Microstructure and Mechanical Properties of AlCrFeNiTix Eutectic High-Entropy Alloys

High-entropy alloys (HEAs) have become important candidates for structural materials of nuclear reactors because of their excellent mechanical properties and irradiation resistance. Recently, eutectic HEAs (EHEAs) have exhibited improved properties by double-phase strengthening. In this study, the effect of Ti on the microstructure and mechanical properties of the EHEAs AlCrFeNi was investigated. Results show that the eutectic microstructure consisted of a disordered body-center cubic (A2) phase and an ordered body-center cubic (B2) phase. Smaller nanoparticles were formed with Ti addition. Ti significantly influenced the microstructure of AlCrFeNi, thus changing the mechanical properties of AlCrFeNi. The compressive strength of AlCrFeNi increased, and the toughness of AlCrFeNi decreased with the increase in Ti content. The application of AlCrFeNiTi0.2 alloy is promising because of its high mechanical properties and superior specific strength. In addition, the AlCrFeNiTix alloys showed great softening resistance at a high temperature (500 °C).