The candidacy of shuffle and shear during compound twinning in hexagonal close-packed structures

摘要: This paper proposes a systematic generalized formulation for calculating both atomic shuffling and shear candidates given compound twinning mode in hexagonal closed-packed metals. Although shuffles play an important role the mobility of dislocations non-symmorphic crystals, their analytical expressions have not been previously derived. The method is illustrated flat planes corrugated which are exemplified by {112¯2} {101¯2} modes, respectively. distinguishes between shuffle displacements net shuffles. While correspond to movements ideal atom positions parent twin lattices, comprise contributions from on overlying can operate along opposite directions those displacements. Thus, direction vanish limiting case, as interestingly case needed second plane b4 dislocation candidate twinning. It found that while displacement vectors be irrational when K1 corrugated, always rational.