Circumferential notched tensile (CNT) testing of cast iron for determination of threshold (K_(ISCC)) for caustic crack propagation

摘要

The paper discusses the use of circumferential notch tensile (CNT) specimens for determination of stress intensity factor (K_I), and novel extension of CNT technique to determination of threshold stress intensity for propagation of stress corrosion cracking (K_(ISCC)). Using CNT testing, K_(ISCC) data have been generated for a cast iron in hot caustic solutions. The features of intergranular propagation of caustic cracks have been established using scanning electron microscopy.