Formability and microstructure evolution for hot gas forming of laser-welded TA15 titanium alloy tubes

A laser-welded TA15 titanium alloy tube with outer diameter of 40 mm and thickness of 2 mm was fabricated successfully by hot U–O forming process combining with laser beam welding. The formability of the laser-welded tube was tested at 800 °C by hot gas free bulging on the self-designed high pressure gas forming platform. Both the microstructure evolutions of the weld seam and basal material during the hot gas free bulging were investigated by...