Low ΔK faceted crack growth in titanium alloys

This communication describes the results of spectrum fatigue loading experiments conducted on cast and hot isostatically pressed Ti–6Al–4V. The purpose of the experiments is to elucidate the nature of faceted crack growth that occurs at low values of ΔK in titanium alloys during cyclic loading. The results clearly show that multiple load cycles are required for the crack to traverse one grain and produce a single facet. The confusing terminology related to low ΔK fatigue fracture topography is reviewed and the term “low ΔK faceted growth” is proposed as a preferred descriptor.