Abstract
R-curves for surface cracks in Ti-6A1-4V titanium alloy were generated for the purpose of studying the resistance of the alloy to their subcritical growth under a monotonically increasing load typical of a proof test. Another purpose was to evaluate Ehret's compliance calibration for measuring the instantaneous size of a surface crack using the unloading slope of a load-versus-clip-gage-opening curve. Another purpose was to study “leak-before-burst” during sustained load and during subcritical crack growth under rising load. Clips were mechanically attached to either side of the surface crack on the face of the specimen. A clip-gage extensometer was used to plot load-versus-clip-gage opening. Slopes were taken periodically by unloading about 10 percent so that subcritical crack growth could be distinguished from crack-tip plastic deformation. The tests were run in accordance with the ASTM Recommended Practice for R-Curve Determination (E 561-78T) as much as possible.
Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
