Crack speed relations inferred from large SEN specimens of A533B steel

A relationship between instantaneous crack tip velocity ( ), dynamic stress intensity factor (K_I, and temperature (T) for A533B steel is estimated using dynamic crack position vs time data measured in a series of very large scale crack arrest tests. The corresponding dynamic stress intensity vs time history and the dynamic arrest toughness for each test are obtained from generation mode elastodynamic analyses based on cubic polynomial fits to the discrete crack position data points. Application mode elastodynamic analytical predictions based on the proposed relationship are within 7% of experimentally measured arrest crack lengths and within 50% of measured arrest times. These predictions represent significant improvements over results obtained using previous preliminary estimates of the relation for A533B. The influence of nonlinear material behavior on the results is also evaluated.