Journal Article

Development of Microstructure and Crystallographic Texture during Stationary Shoulder Friction Stir Welding of Ti-6Al-4V

Wynne, B. P., Rainforth, W. M., Davies, P. S., Threadgill, P. L., Thomas, M. J.

2011

Overview

Electron backscattering diffraction (EBSD) was used to study a stationary shoulder friction stir weld in Ti-6Al-4V. Weld temperatures exceeded the β -transus, resulting in a supertransus zone (STZ) that encompassed all of the thermomechanically affected zone (TMAZ) and a portion of the heat-affected zone (HAZ). Standard EBSD provided limited information on the material behavior at high temperature in the β phase field, so in-house software was used to reconstruct the crystallographic orientations of the high-temperature β phase. The portion of the HAZ that lay within the STZ exhibited the same β texture at high temperature as the retained β phase in the unaffected parent material. In the TMAZ, material was deformed in the high-temperature β phase field and, on cooling, transformed to a fully lamellar microstructure. The β textures at high temperature were dominated by the D 2 simple shear texture component. The α phase textures in the fully lamellar microstructure that formed on cooling were inherited from the shear textures of the β phase, but significant variant selection occurred.

• Publisher: Springer US,Springer Nature B.V
• Subject: Characterization and Evaluation of Materials / Chemistry and Materials Science / Cooling / Deformation / Friction stir welding / High temperature / Materials Science / Metallic Materials / Microstructure / Nanotechnology / Structural Materials / Surfaces and Interfaces / Thin Films / Titanium alloys