Slip transmission across fcc/bcc interfaces with varying interface shear strengths

Interfaces with relatively low shear strengths can be strong barriers to slip transmission because of core spreading of the dislocation within the interface. Using atomistic modeling and elasticity-based calculations we have studied the influence of interface shear strength on the slip transmission of a single dislocation across fcc/bcc interfaces. “Tunable” interatomic potentials were employed to vary the interface shear strength for the same interface crystallography. The results show that the slip transmission barrier increases with decreasing shear strength of the interface. The results reveal a mechanism for the variations in ultra-high strengths observed in nanoscale fcc/bcc multilayers.