Fracture-Flow Relationships for A533B Pressure Vessel Steel

Abstract

The large scatter emerging from KIc measurements for heavy walled pressure vessel steels is examined in view of new data for A533B. Extensive plastic flow data at −220 deg F and 80 deg F has revealed a marked, and apparently harmonic, flow strength variation repeated at strain rate intervals in ratio of about 20. The tension skewed path over these ridges is related to the KIc behavior, for which a corresponding variational pattern with loading rate K̇ is observed. The variational pattern, or rate spectrum effect, is large compared to the average speed sensitivity of KIc , suggesting that transition temperatures values could be measured at a more moderate, though rapid, loading rate to avoid the inertial ringing effects of impact.