Fabrication of 3D printed complex concentrated alloys using oxide precursors

Abstract

In this article we report on the first reduction of a compositionally complex concentrated CoCrFeMnNi alloy processed entirely from oxide precursors and printed using materials extrusion additive manufacturing (AM) techniques. The chemical and structural properties of this material are explored, while transmission electron microscopy (TEM) is used to investigate potential chemical segregation within the well-annealed grains. The relative thermodynamic stability of Mn and Cr oxides would suggest that MnO and Cr2O3 will not reduce in a hydrogen atmosphere. However, we find that the unique local thermodynamic environment present in the samples allows for full reduction of Mn and Cr while diffusion into the grain allows for the development of a single-phase FCC structure.