A special class of multicomponent concentrated solid solution alloys (CSAs), of which the recently discovered high entropy alloy (HEA) are exemplars, offers a new paradigm for the development of next generation structural materials. Although the number of single-phase CSAs and HEAs is limited, those that do exist often exhibit remarkable electronic, magnetic transport and mechanical properties. In this talk, the mechanical properties and strengthening mechanisms of the single phase concentrated solid solution alloys and high entropy alloys will be discussed based on the mismatches of the atomic sizes and elastic constants. Based on the strengthening mechanisms, combined with thermodynamic calculation, we further develop concentrated solid solution alloys with very superior high strengths, work hardening capacity and good ductility.
Research supported by the US Department of Energy, BES, Materials Sciences and Engineering Division.