Influence of the Ball-to-Powder Ratio on Phase Formation and Functional Properties of AlCoFeNiTi High-Entropy Alloys Synthesized by High-Energy Ball Milling

Herein, AlCoFeNiTi high-entropy alloy (HEA) samples were prepared by mechanical alloying using high ball-to-powder (BtP) ratios to investigate the effects of this method on phase formation, magnetic properties, and electrical conductivity. X-ray diffraction revealed that the prepared samples contained amorphous, body-centered cubic (BCC), and face-centered cubic (FCC) phases. The samples were dominated by the amorphous phase, indicating the influence of high BtP ratios on their structure. All the samples exhibited semihard magnetic properties, with the saturation magnetization (M s) value depending on the milling time. The sample synthesized at a milling time of 30 h exhibited the highest M s value of 60.1 emu g-1. The switching field distribution was employed to clarify the contributions of the BCC, FCC, and amorphous phases to the magnetic properties. The results showed that the BCC and amorphous phases contributed to over 95% of the sample magnetism, of which approximately 75% was attributed to the BCC phase. Notably, the magnetic properties of amorphous AlCoFeNiTi HEAs were demonstrated for the first time in this study.