Microstructure of Ti6Al4V after Ultrasound-Aided Deep Rolling
Ti6Al4V titanium alloy was treated by an ultrasound-aided deep rolling (UADR) process. The microstructure of UADR treated specimen was observed via using scanning electron microscopy (SEM), X-ray diffraction (XRD) and transmission electron microscopy (TEM). Results show that ultrasound-aided deep rolling produced nanocrystallized microstructure of grain scale typically less than 20 nm on the immediate surface of Ti6Al4V. A nanometer to submicron gradient structured layer penetrating to a depth of about 150 μm was formed after UADR treatment. The above improvements of surface microstructure of the UADR treated specimen is believed to be beneficial to its anti-fatigue performance.