Microstructures and mechanical properties of CrFeNi2Nbx eutectic multicomponent alloys

Abstract

The effects of Nb content on microstructures and resultant mechanical properties in Co-free CrFeNi2Nbx (x = 0, 0.2, 0.4, 0.55, 0.6, and 0.8) eutectic multicomponent alloys were investigated at room temperature. With increasing Nb content, the initial microstructure of a single face-centered cubic phase varied from hypoeutectic (0.2 <x < 0.6) to hypereutectic (x > 0.6) with the formation of Fe2Nb-type Laves phase, and the compressive strength and hardness increased at the expense of ductility reduction. Although the overall mechanical properties of the alloys were inferior to those of Co-containing CoCrFeNiNbx alloys, a comparable maximum fracture strength (2060.6 MPa) was achieved in the CrFeNi2Nb0.6 alloy, which showed an ultrafine full eutectic lamellar structure.