ELECTRON BACKSCATTERING PATTERN IDENTIFICATION OF SURFACE MORPHOLOGY OF FATIGUE CRACKS IN TA6V

Abstract

Abstract— Fatigue crack growth in an α+β titanium alloy (TA6V) with three microstructural conditions is studied in high vacuum at 300°C. The faster growth rates are observed in the material with a low content of primary α phase and a fine equiaxed microstructure. Near the threshold regime, a slow crystallographic Stage I‐like propagation is observed in the three microstructural types where slip occurs along a single‐plane system which develops within the α grains. These crystallographic facets are identified using an electron backscattering pattern (EBSP) technique and were found to lie on basal planes.