Evolution of texture and tensile properties of cold-rotary swaged Ti–6Al–4V alloy seamless tubing after annealing at different temperatures

Abstract

The effect of texture evolution, recrystallization behavior and deformation on the mechanical properties of cold rotary swaged Ti–6Al–4V tubing during annealing was studied by X-ray diffraction (XRD) and electron backscatter diffraction (EBSD). The prismatic slip (1 1(_) 00) [112(_) 0], pyramidal slip(10 1(_) 1) [1(_) 21(_) 0] with the largest Schmid factor values (SF) and {101(_) 2} twining structure can be obtained after annealing at 650 °C. The high plasticity of the Ti–6Al–4V tubing can be attributed to the combined effect of slip structure and twining structure. As a result, Ti–6Al–4V tubing has excellent tensile properties and achieves a compromise between strength and ductility. Meanwhile, the radial texture produced by cold rotary swaging has almost no change though slight recrystallization occurs at this temperature. After annealing at 750 °C, the content of {10 1(_) 2} twining decreases significantly, and the recrystallization reduces the dislocation and grain boundary strengthening effects. This work is of theoretical significance and practical value for optimizing the annealing processes of cold rotary swagged Ti–6Al–4V tubing and developing advanced aerospace hydraulic systems with higher operating pressures.