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 beta 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 mu m wide at the mid-section of the weld, and increasing away from the centre to about 1000 mu m 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.