Alloying and thermal behaviour of CoCrFeNiMn_0.5Ti_0.5 high-entropy alloy synthesised by mechanical alloying

Abstract

An inequi-atomic CoCrFeNiMn_0.5Ti_0.5 high-entropy alloy (HEA) was synthesised by mechanical alloying. The structural and morphological evolution of the alloy powder during the mechanical alloying process and the thermal behaviour of 60 h ball-milled HEA powder were investigated systematically. A simple body-centred cubic solid solution HEA structure was obtained when the blended powder was ball-milled longer than 36 h. A 60 h ball-milled powder had an average particle size of 3 μm and consisted of hard agglomerated crystalline particles with a crystal size of < 20 nm. The body-centred cubic phase transformed into a face-centred cubic phase when the powder was annealed for 1 h at a temperature of 700°C; the liquidus point of the face-centred cubic phases was 1402.8°C.

Keywords:

• High-entropy alloys
• Mechanical alloying
• Microstructure
• Morphology
• Thermal analysis