Determination of crystallographic orientation of dwell-fatigue fracture facets in Ti-6242 alloy

A technique to determine the crystallographic orientation of the fracture facets has been described. The spatial orientation of the facet plane is determined in a scanning electron microscope (SEM) using a quantitative tilt fractography technique. The crystallographic orientation of the grain, across which a particular fracture facet had been produced, is determined using the electron backscattered diffraction (EBSD) technique in an SEM. These two pieces of information were combined to obtain the crystallographic orientation of the fracture facet normal. This technique was used for the characterization of dwell-fatigue fracture facets at the crack-initiation site in Ti-6242 alloy. Our results indicate that these facets are not exactly aligned with the basal plane, but are inclined at ∼10° to it.