
Design of transformation-induced plasticity-assisted dual-phase high-entropy alloys

Deformation micro-mechanisms in the TRIP-DP-HEA with increasing tensile deformation at room temperature. (a) EBSD phase maps revealing the deformation-induced martensitic transformation as a function of deformation. (b) ECCI analyses showing the evolution of defect substructures in the FCC and HCP phases. (c) Schematic sketches illustrating the sequence of micro-processes in the TRIP-DP-HEA.
HEAs are originally proposed to benefit from phase-stabilization through entropy-maximization. Yet, the concept is overturned in this project by designing a massive solid solution strengthened, transformation-induced plasticity-assisted, dual-phase HEA (TRIP-DP-HEA). We decrease phase stability to achieve two key benefits: (i) interface hardening due to a dual-phase microstructure (that results from reduced thermal-stability of the high temperature phase); (ii) transformation-induced hardening (that results from the reduced mechanical-stability of the room temperature phase). This combines the best of two worlds: extensive hardening of advanced steels owing to decreased phase stability, and massive solid solution strengthening of HEAs.