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

The paper discusses the use of circumferential notch tensile (CNT) specimens for determination of stress intensity factor (KI), and novel extension of CNT technique to determination of threshold stress intensity for propagation of stress corrosion cracking (KISCC). Using CNT testing, KISCC 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.