Mechanical Behavior of Al_0.5CoCrFeNi HEA During Warm Deformation

The serrated flow during tensile testing of Al_0.5CoCrFeNi high-entropy alloy at 200–500°C and strain rates of 10⁻²–10⁻⁴ s⁻¹ was evaluated in this study. The temperature range of serration flow in the stress-strain curve changed as the strain rate increased. In addition, due to increased temperature and chromium enrichment of phase B2, the strength was considerably improved. Conversely, at 400–500°C, the elongation was significantly reduced while the strength increased from 300 MPa to 500 MPa to approximately 800 MPa. These changes were attributed to the precipitation of phase B2 and the enrichment of the B2 phase with Cr.