Modelling of crack path in layered architectures composed of dissimilar
materials
Abstract
In order to make full use of the potential fatigue crack growth
resistance provided by layered architectures, a validated crack path
simulation algorithm for crack propagation through different elements of
the layered architectures was established. The crack path approaching a
material interface was predicted by using the maximum tangential strain
(MTSN) criterion and the crack behaviour at the interface was simulated
by a developed two-step method (a modified stress-and-energy-based
cohesive zone method considering the change in direction of an interface
penetrating crack). The crack path simulation by using this algorithm in
layered example architectures indicates: 1) there are two criteria zones
for the transition between crack deflection and penetration in terms of
the relationship between interfacial strength and toughness; 2) the
likelihood of a crack deflecting out of the interface will increase with
the propagation of an interfacial crack and 3) the architecture
difference which affects shielding or anti-shielding behaviour has a
significant effect on crack deflection or penetration events.