Transmission electron microscopy of single-slip oriented Ni3Al single crystals cyclically deformed at room temperature revealed a high density of dislocation dipoles and point defect clusters. The majority of the defect clusters were identified by weak-beam TEM to be of vacancy type. The observations of circular perfect dislocation loops, Frank loops, and spherical voids revealed the evidence of vacancy condensation during fatigue cycling at room temperature. Together with SEM observations of surface topography, it is suggested that fatigue crack initiation in Ni3Al single crystals can be rationalized by formation of microvoids at PSB/matrix interfaces.
This is a preview of subscription content, access via your institution.
Buy single article
Instant access to the full article PDF.
Tax calculation will be finalised during checkout.
L. H. Hsiung and N. S. Stoloff, ICSMA 8, Tampere, Finland, p. 683, (1988), 1, Oxford, (ed. P.O. Kettunen, et al.) Pergamon.
V. Paidar, D. P. Pope and V. Vitek, Acta Metall., 32, p. 435, (1984).
J. Polak, Mat. Sci. and Eng., 92, p. 71, (1987).
L. M. Hsiung and N. S. Stoloff, to be published.
About this article
Cite this article
Hsiung, L.M., Stoloff, N.S. Electron Microscopy Study of Fatigue Crack Initiation in Ni3Al Single Crystals. MRS Online Proceedings Library 133, 261 (1988). https://doi.org/10.1557/PROC-133-261