|About this Abstract
||2017 TMS Annual Meeting & Exhibition
||The John Cahn Memorial Symposium
||Energetic Trends for Twin Boundaries in HCP Metals
||Maarten de Jong, Liang Qi, Axel van de Walle, Mark Asta
|On-Site Speaker (Planned)
This talk will describe the results of computational studies exploring trends in the the energetics of twin boundaries in hcp transition metals and alloys. The calculations employ a recently developed method for modeling interfacial energies in substitutional alloys from first-principles calculations based on the special quasirandom structure approach. The calculations reveal anomalously low values of twin boundary energies for specific orientations, for hcp metals and alloys with d-band filling near that of the group VII metal rhenium. The origins of this behavior are investigated and linked to the theory of the trends in bulk structural energetics across the transition-metal series, which predicts the stability of topologically close-packed phases containing atomic coordination polyhedra similar to those found in the stable twins in this region of the periodic table. The results are discussed in light of experimental observations of deformation microstructures, and the implications for alloy design are described.