Multiscale microstructure-based modelling of cleavage in high strength steels

The need for more accurate cleavage modelling is particularly acute for a new generation of high-strength steels because they obtain their favourable properties through complex, multi-phase microstructures. One of the challenges in cleavage modelling is the strong sensitivity to material characteristics at the microlevel. This thesis proposes a...

Microstructure-based cleavage parameters in bainitic, martensitic, and ferritic steels

Multi-barrier cleavage models consider cleavage fracture which is characterized by a series of microscale events. One of the challenges for multi-barrier cleavage models is the strong variations of cleavage parameters across different types of steels. The source and magnitude of the variations have not been studied systematically. In the...

Microstructure-informed statistical modelling of cleavage fracture in high strength steels considering through-thickness inhomogeneities

Thick section S690 QT steel is modelled with a modified multibarrier model that is based on the weakest-link mechanism. Segregation bands are modelled as discrete layers which have different grain size, yield properties, and local fracture parameters from outside of the bands. The results show that embrittlement from segregation bands can...