Research analyst, Northrop Corp., Hawthorne, Calif.
Professor of mechanics, Lehigh University, Bethlehem, Pa.
A test procedure is outlined by which the rate of fatigue crack growth over a range of stress ratios and stress intensities can be determined expeditiously using a small number of specimens. This procedure was developed to avoid or circumvent the effects of load interactions on fatigue crack growth, and was used to develop data on a mill annealed Ti-6Al-4V alloy plate. Experimental data suggest that the rates of fatigue crack growth among the various stress ratios may be correlated in terms of an effective stress intensity range, Δ Keff, at given values of Kmax.
This procedure is not to be used, however, for determining the corrosion fatigue crack growth characteristics of alloys when non-steady-state effects are significant.
Paper ID: JTE10076J