Microstructure and microtexture of linear friction welded Ti-6Al-4V

In this study, the microstructural features of linear friction welded Ti-6Al-4V joints have been investigated using X-ray diffraction (XRD), scanning electron microscopy (SEM) including electron backscatter diffraction (EBSD), and transmission electron microscopy (TEM). It has been found that the volume fraction of the β phase in the weld regions is much lower than that in the base metal. The chemical composition at the weld line region was found to be homogeneous suggesting that a martensitic transformation occurred during welding. Strong crystallographic textures were observed across the weld line, with the width of the strongly textured region being approximately 500 μm wide at the mid-section of the weld, and increasing away from the centre to about 1000μm at the edge of the weld. A very strong {0001}<1010> texture component was identified in the weld line zone and the thermomechanically affected zone.