EUROPEAN CONGRESS AND EXHIBITION ON ADVANCED MATERIALS AND PROCESSES - EUROMAT 2021

We first report the microstructure and mechanical properties of a non-equimolar eutectic high-entropy alloy (EHEA) CoCrFeNiTaAl fabricated by additive manufacture. The as-printed EHEA consists of a nanostructured network-like Laves phase (width ~ 30 nm) embedded in an fcc phase matrix (average grain size of 17μm). The alloy exhibits an excellent mechanical property (yield strength ~ 2.3 GPa, plasticity > 50%) via compressive micro-pillar test. The underlying mechanisms are unraveled based on the coupling between the extremely fine in-situ composite of the hard Laves phase and ductile fcc matrix derived from the eutectic reaction and fast cooling speed in additive manufacture processing. The eutectic high-entropy alloy is believed to be a promising feedstock material for metal additive manufacturing.