LATTICE TRAPPING ON THE {011} CLEAVAGE PLANE IN NiAl

Abstract

The crack tip response of cracks on the {110} cleavage plane for five different propagation directions in NiAl was studied atomistically under mode I opening loading conditions. The region near the crack tip was described by an Embedded Atom Method (EAM) potential, and the FEAt (Finite Element-Atomistic) coupling scheme provided the atomistic core region with realistic boundary conditions. In agreement with experimental observations, perfectly brittle cleavage is observed for the {110} crack plane. A simple spring lattice trapping model was developed which allows qualitative predictions on the lattice trapping in dependence of the projected bonding distance along the crack propagation direction.