Microstructure and Mechanical Properties of EBF3 Ti-6Al-4V Parts Subjected to Ultrasonic Impact Treatment Assisted with Pulsed Electric Current Exposure

The effect of an ultrasonic impact treatment assisted with pulsed electric current exposure on themicrostructure, elemental, phase composition and mechanical properties of EBF3 Ti-6Al-4V parts has been studied. It was shown that the coating was formed by the rapid solidification of the microscale molten pool within outermost surface layer, while the impact process formed the plastically deformed sublayer. Formation of coating containing W2C, W, nonstoichiometric carbide WC1-x, metastable W-2(C,O), and titanium oxide TiO2 phases on the surface of EB(F)3 Ti-6Al-4V parts subjected to electropulsing assisted ultrasonic impact treatment was revealed using X-ray diffraction method. The microhardness of the coating and plastically deformed sublayer is equal to 15 and 6 GPa, correspondently. The depth of the hardened surface layer was 200 mu m.