Abstract
Results from mathematical models and computer simulations of fracture in polycrystalline steels are presented for a range of temperatures. The proportions of intergranular and intragranular failure predicted are compared with experimental results for brittle fracture, ductile fracture and in the transition region. Interactive software to create two-dimensional polycrystalline models, which allow a range of physical to be varied independently, is described. The results include those for model materials chosen to match steels used by the power generation industry. The models simulate segregation and cavitation effects in steel and fracture of weldments and their associated heat-affected zones.