Fractographic analysis of gaseous hydrogen induced cracking in 18Ni maraging steelElectron microscope fractographic analysis supplemented an extensive study of the kinetics of gaseous hydrogen assisted cracking in 18Ni maraging steel. Temperature determined the crack path morphology in each steel which, in turn, was directly related to the temperature dependence of the crack growth rate. Crack growth in the low temperature regime proceeded along prior austenite grain boundaries. Increasing the temperature above a critical value produced a continuously increasing proportion of transgranular quasi-cleavage associated with lath martensite boundaries. The amount of transgranular cracking was qualitatively correlated with the degree of temperature-induced deviation from Arrhenius behavior. Fractographic observations are interpreted in terms of hypothesized mechanisms for gaseous hydrogen embrittlement. It is concluded that hydrogen segregation to prior austenite and lath martensite boundaries must be considered as a significant factor in developing mechanisms for gaseous embrittlement of high strength steels.
Document ID
19790040266
Acquisition Source
Legacy CDMS
Document Type
Conference Proceedings
Authors
Gangloff, R. P. (GE Corporate Research and Development Center Schenectady, N.Y., United States)
Wei, R. P. (Lehigh University Bethlehem, Pa., United States)
Date Acquired
August 9, 2013
Publication Date
January 1, 1978
Subject Category
Metallic Materials
Meeting Information
Meeting: Fractography in failure analysis; Symposium