Structural Features and Solid-Solution Hardening of High-Entropy CrMnFeCoNi Alloy

The phase composition, microstructure, and mechanical properties of the single-phase CrMnFeCoNi high-entropy alloy with fcc lattice produced by argon-arc vacuum melting are studied. The alloy solid-solution hardening mechanism is analyzed. The abnormally high athermic solid-solution hardening of the alloy is due to variation in the Burgers vector along the dislocation line and a vector component perpendicular to the slip plane. The activation energy of dislocation movement and activation volume are calculated. The activation energy of dislocation movement is close to the activation energy of pure metals with fcc lattices, and the activation volume is significantly lower compared to that of pure metals because picosized distortions grow in the crystal lattice of the multicomponent alloy. The ratio of hardness and yield stress for this alloy is examined.