Design Of Fe7cr7-Xni4+Xtimo High Entropy Alloys With Modulated Fracture Toughness Through Adjustment Of Its Microstructure

Authors:

E. Frutos (1), D. Cuenca-Fernandez (1), N. Encinas (1), J. Cornide (1)

1-Surface Engineering and Nanostructured Materials Research Group, Faculty of Chemical Sciences, Complutense University of Madrid, Spain

Abstract:

Strengthened high entropy alloys (HEAs), represent a new paradigm for simultaneously achieving high strength and ductility, thereby circumventing this well-known trade-off in conventional and single-phase HEAs alloys. However, dynamic strengthening mechanisms and phase-boundary interactions during external loading remain unclear for these multiphase systems. The large fraction of phase boundary significantly impacts plastic flow in these systems. In this study, the microstructure, based on a mixture of ordered FCC/BCC ((L12, L21)/B2) phases and s phase, and small-scale mechanical behaviour has been evaluated for Fe7Cr7-xNi4+xTiMo (x=0, & 2) high entropy alloys obtained from of mechanically alloyed powders by spark plasma sintering (SPS). The use of nano and macro-indentation tests has allowed us to characterize the values of hardness and fracture toughness shown by the different (L12, L21)/(B2,s)ratios presented by high-entropy Fe-rich alloys.

DOI:

https://doi.org/10.59499/EP246280981