Direct laser deposited bulk CoCrFeNiNb_x high entropy alloys

Bulk CoCrFeNiNb_x high entropy alloys (HEAs) were successfully fabricated by direct laser deposition. The microstructures, mechanical properties and work-hardening behavior of the as-deposited CoCrFeNiNb_x HEAs were investigated. The uniform and fully compact microstructures were characterized in both longitudinal and transverse sections. Apparent pores and microcracks are absent in all samples. Moreover, a transition from columnar structure to equiaxed structure was observed with the increasing addition of Nb element. Room temperature tensile tests showed the excellent combination of strength and ductility compared with the as-cast counterparts. The CoCrFeNiNb_x HEAs show better printability and excellent mechanical properties than other high entropy alloys within direct laser deposition processing.