The effects of warm pre-stressing on cleavage fracture. Part 2: finite element analysis

Finite element analyses have been performed to simulate and verify the findings of the extensive experimental programme aimed to characterise the mechanical parameters and the cleavage fracture response following warm pre-stressing of two steels, BS1501 and A533B as detailed in part 1 [The Effects of Warm Pre-Stressing on Cleavage Fracture. Part 1: Evaluation of Experiments, companion paper]. A stress matching approach to predicting the fracture response of the as received, as well as the warm pre-stressed specimens is suggested. Using the stress distributions from the finite element analyses prediction of fracture after WPS is examined and results are compared to the experimental data and those obtained by combining the Chell [Int. J. Fract. 17 (1) (1981) 61; Proc. 4th Int. Conf. Pres. Ves. Technol., 1980, p. 117; Int. J. Pres. Ves. Pip. 23 (1986) 121] WPS model with the Wallin [Defect Assessment in Components, Fundamentals and Applications, ESIS/EGF 9, Mechanical Engineering Publications, London, 1991, p. 415] failure probability model described in part 1 [The Effects of Warm Pre-Stressing on Cleavage Fracture. Part 1: Evaluation of Experiments, companion paper]. The significance of residual stress field in enhancing of cleavage fracture toughness following warm pre-stressing has been highlighted. Using the appropriate finite element models, the role of sub-critical crack growth and crack tip blunting are also investigated.