Developing CoCrFeNi High Entropy Alloy with Mo and Nb via In-situ Alloying in Laser Powder Bed Fusion (PBF-LB/M) and Evaluating Its High Temperature Properties

Abstract

High Entropy Alloys (HEAs), a novel class of materials diverging from conventional alloying concept of single principal element, show immense potential, especially in high-temperature applications. This study leverages Laser Powder Bed Fusion (PBF-LB/M) to manufacture a CoCrFeNi-based HEA alloyed with minor additions of Mo and Nb using commercial powders like Ni-base superalloys and 316L in a cost-effective approach. The as-printed compositions resulted in alloys with single-phase FCC upon printing. Tensile tests at 700°C, 800°C, and 900°C reveal enhanced strength compared to similar alloys in the literature, facilitated by Mo and Nb-rich precipitates. This work not only advances understanding of HEAs but also offers insights for future alloy design, highlighting the efficiency of PBF-LB/M in creating intricate components with complex compositions and improved mechanical properties for high-temperature applications with relative ease.