Constitutive Equation and Processing Map of CoCrFeNiMo_0.3 High Entropy Alloy Based on The Thermoplastic Deformation

Abstract

The unique characteristics of high entropy alloys are challenging the field of traditional materials science and are expected to apply innovations in fields such as aerospace and defense, making them one of the strong candidates. The thermoplastic deformation mechanisms and processing maps of CoCrFNiMo0.3 alloy were studied at a temperature (T) ranging from 950 - 1250 °C and a strain rate ( ε ˙ ) ranging from 0.001 - 0.1 s−1. A sharp rise is observed in the flow curve in the early stage, as the strain increases, slowly increasing flow stress due to the presence of dynamic softening, then turns to decrease, finally reaches a steady state. The optimal processing area was at 1050 - 1250 °C and 0.001 - 0.1 s−1, and there is an unstable area appearing at 950 - 1050 °C and 0.01 - 0.1 s−1. The η in the hot processing region are high, and they are not in the instability region.