Microstructure evolution and magnetic characteristics of a novel high entropy alloy produced by mechanical alloying and spark plasma sintering

In this research, CoMoMnNiV high entropy alloys were successfully prepared by mechanical alloying (MA) and spark plasma sintering (SPS). The microstructure, phases and magnetic properties of the as-milled powders and bulk sample were examined, employing X-ray diffraction, differential scanning calorimeter (DSC), scanning electron microscopy, and Vibrating Sample Magnetometer (VSM) techniques. The resultant phase following MA exhibits a dual-phase microstructure comprising BCC and FCC solid solutions, with individual crystal dimensions below 18 nm. Thermal stability assessment via DSC reveals the alloy robustness up to 1216 °C. The SPS was performed on the MA samples at 980 °C and 50 MPa pressure, and their density was determined to be 89.64 %. The sample subjected to a milling duration of 40 h demonstrated a saturation magnetization of 25.977 electromagnetic units per gram (emu/g) and a coercivity of 371.5 Oersteds (Oe).