Phase evolution and thermal stability of mechanically alloyed CoCrCuFeNi high entropy alloy

Fast mechanical synthesis, structure evolution, and thermal stability of nanostructured CoCrFeNiCu high entropy alloy

“…Among HEAs, CoCrFeNiCu composition has been extensively studied earlier as HEA thin films and coatings deposited by magnetron sputtering [27,28], as volume HEA materials (mechanically alloyed powders and consolidated bulk samples) [29][30][31][32][33]. Different amounts of Ti and Al are usually added to study the phase evolution, mechanical and magnetic properties of designed systems [16,17].…”

“…The most of studied CoCrFeNiCu-based alloys were synthesized by arc melting followed by quenching [29][30][31]. Only a few studies (mostly controversial) on the structure and stability of mechanically alloyed CoCrFeNiCu HEAs have been reported so far [32][33][34].…”

“…The CoCrFeNiCu HEA prepared by MA for 65 h [32] represented a mixture of bcc (as a main phase) and fcc (minor) phases. Results of in-situ high temperature X-ray diffraction (HT XRD) have shown low thermal stability of HEA powders (up to 350 °C) due to diffusion-assisted transformation into precipitates of the σ phase.…”

“…Results of in-situ high temperature X-ray diffraction (HT XRD) have shown low thermal stability of HEA powders (up to 350 °C) due to diffusion-assisted transformation into precipitates of the σ phase. Eventually, annealing at 800 °C for 2 h led to the formation of the simple fcc phase with a negligibly low admixture of the σ phase [32].…”

“…In view of the inconsistency between the available data [32][33][34] on the structure/phase formation and thermal stability in mechanically alloyed CoCrFeNiCu HEAs, in this communication we report on the fast synthesis of equiatomic CoCrFeNiCu high entropy alloy by high energy ball milling and its structural characterization and phase evolution by X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy dispersive X-Ray (EDX). The structural/phase evolution and thermal stability of HEBM CoCrFeNiCu HEA powders were studied by in-situ HT XRD, differential scanning calorimetry (DSC) and through SPS consolidation.…”