The universality of strength and plastic deformation in FCC concentrated solid solution (CSS) alloys at room and cryogenic temperatures

Abstract

To reveal if universal rules may exist in face centered cubic (FCC) concentrated solid solution (CSS) alloys for strength and plastic deformation at room and cryogenic temperatures, we select a FCC CSS superalloy Haynes 188 to demonstrate the deformation mechanisms from atomic to micrometer scales. In FCC CSS alloys, the yield strength (YS) is intrinsically determined by atomic/modulus mismatches and affected extrinsically by grain size; the tensile strength and elongation to fracture (EF) are governed by the plastic process where low stacking fault energy is beneficial. Moreover, almost all CSS alloys show that YS and EF increase simultaneously with the decrease in the temperature. Our findings may expand alloy application and can be used as a design strategy for stronger and tougher alloys.