Computational modelling of fracture in polycrystalline materials

This review provides a brief survey of the computational methods which have been adopted to model fracture in materials, particularly polycrystalline metals and alloys, and considers in greater detail the use of geometrical modelling. The different modes of fracture, transgranular and intergranular brittle and ductile, are discussed, together with the modelling tools adopted for macroscale, microscale and nanoscale applications. The procedures which have been used for creating computer models of two- and three-dimensional polycrystalline materials and for propagating cracks through them are then outlined. Applications of these methods to investigate the propagation of cleavage cracks across grain boundaries, to study the influence of texture, grain shape, impurity segregation and prior creep cavitation, to examine the ductile-to-brittle transition region in ferritic steels and to consider the influence of work hardening on ductile fracture are then presented. The predictions are compared with experimental results and proposals for future studies are discussed.