FATIGUE CRACK-PROPAGATION OF METASTABLE BETA TITANIUM-VANADIUM ALLOYS

The fatigue crack propagation behavior of three titanium-vanadium alloys (24, 28, and 32 wt pct V) which have tensile deformation modes ranging from coarse twinning to wavy and planar slip has been measured in laboratory air and correlated with their low cycle fatigue properties and microstructure. The fatigue crack growth rate of alloys with similar microstructures but different deformation modes, and of alloys with similar deformation modes but different microstructures have been compared. Increasing the deformation barrier mean free path and improving low cycle fatigue properties has been observed to reduce the fatigue crack growth rate at low and inter mediate ΔK levels. The fatigue crack growth data have been compared with that calculated from equations which use microstructure and low cycle fatigue parameters. The predictive capability of these equations which contain only measurable parameters has been found to be quite adequate. © 1979 American Society for Metals and the Metallurgical Society of AIME.