Alloying effects of Ta on the mechanical properties of gamma ' Co-3(Al, W): A first-principles study

摘要

The effects of Ta on the ideal strength, elastic properties and electronic structure of gamma'-Co-3(Al, W) were investigated using first-principles methods. The results indicate that the mechanical strength of Co-3(Al, W) is restricted with the valence charge depletion of Co-Al bonds. The predicted enhancement of mechanical property by Ta additions is attributed to the Ta5d electrons participating in the ring-like bonding between Co3d and W5d. These results provide a new insight into the understanding of alloying effects on Co-base superalloys. (C) 2015 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.