Enhancing tensile properties of laser additive manufactured FeCoNiCrMn high entropy alloy via adding Fe-based metallic glass

Abstract

It has always been difficult to significantly improve the tensile strength of FeCoNiCrMn high entropy alloy (HEA) by traditional technical methods. Here, high-strength Fe-based metallic glass (MG) was precisely selected as the strengthening phase to reinforce the mechanical properties of FeCoNiCrMn HEA fabricated by laser additive manufacturing (LAM) technology. The results showed that although the addition of Fe-based MG with 5 wt% did not change the original phase composition of HEA, it facilitated grain refinement to a great extent. Of special significance was that the strength and ductility of HEA-MG exhibited a synergistic enhancement (σy, σUTS and εf were increased by 23.8 %, 28.4 % and 31.0 %, respectively) after Fe-based MG addition, deriving from the grain refinement, increased the dislocation density and formation of deformation twins.