High-temperature crack-arrest behavior of prototypical and degraded (simulated) reactor pressure vessel steels

Sixteen wide-plate crack-arrest tests have been completed, ten utilizing specimens fabricated from A533B Class 1 material and six fabricated from a low-upper-shelf base material. Each test utilized a single-edge notched specimen that was subjected to a linear thermal gradient along the plane of crack propagation. Test results exhibit an increase in crack-arrest toughness ( K Ia ) with temperature, with the rate of increase becoming greater as the temperature increases. When the wide-plate test results are compared with other large-specimen results, the data show a consistent trend in which the K Ia data extend above the limit provided in ASME Section XI.