ON THE TEMPERATURE DEPENDENCE OF CLEAVAGE FRACTURE TOUGHNESS OF SILICON STEEL

Results of experiments indicated that the analysis of the cleavage fracture of silicon steel seems to be hard to solve by RKR model. The Weibull statistical theory was introduced to describe the volume effect of the cleavage fracture stress determined by smooth tensile and notched bend specimens. The temperature dependence of the cleavage fracture toughness and its scatter band of silicon steel is formulated by applying the HRR theory and the Rice-Johnson's stress analysis for the blunted crack tip zone, as well as by combining with the Weibull's statistical model. The experimental data are in agreement with the prediction.