Microstructural Evolution and Mechanical Behaviour of Near-Eutectic High Entropy Alloy

Abstract In the current work, thermal stability of eutectic regions and precipitation mechanical behaviour near high-entropy alloy is studied. The solidified as FCC underwent sequential ordering to L1 2 with order–disorder transition temperature between 700°C 1000°C. Cooling rate, variation in concentration boundary layer, gradient interfacial energy were attributed define morphology (L1 B2). Thermal exposure resulted homogeneous acicular Al-Ni-rich B2 phase within proeutectic irregular regions. preferential was lower higher lattice strain associated these FCC: fraction after heat treatment similar that alloy. Furthermore, lamellar degradation, globularization Ostwald ripening observed treatment. Lamellar degradation occurred via mechanisms like cylinderization, edge spheroidization, termination migration splitting. experimental observations on evolution, transformation matched well CALPHAD predictions except for σ formation. during enhanced However, work hardening rate superior as-cast