Crack deflection and crack paths in anisotropic aluminum alloy AA7010-T7452: Uncertainties and stochastic aspects

Crack paths in CT-specimens are investigated for AA7010-T7452 aluminum alloy. Two quenching temperatures effectuate different degrees of anisotropy of fracture toughness, having a crucial impact on crack deflection under initial mode-I loading. To incorporate the angular characteristic of crack growth resistance into FE simulations, eleven values of the fracture toughness have been recorded. It is found by stochastic and deterministic simulations, as well as by analytical derivations, that crack paths may be sensitive to the angular distribution of toughness and slight deviations from supposed crack orientation angles, partly leading to crack path instability. Peculiarities of experimental findings are explained on this basis.