ULTRAFINE-GRAINED Ti-6Al-4V-ALLOY USED FOR PRODUCTION OF COMPLEX-SHAPED ARTICLES WITH ENHANCED SERVICE PROPERTIES

This work presents the results of investigation of microstructure and mechanical prop- erties of gas-turbine engine (GTE) blades made from Ti-6Al-4V alloy with an ultrafine-grained (UFG) structure fabricated by means of severe plastic deformation. A possibility of efficient shap- ing of a blade out of the UFG alloy by means of isothermal stamping at lowered temperatures with retention of the UFG structure in a blade-item was demonstrated. Comparative fatigue tests of blades manufactured by conventional and pilot technologies were conducted, which demon- strated increase of the fatigue endurance in blades with the UFG structure by almost 30%. The V- and T-notch impact strength of pilot blades retained the increased values (no less than 320 and 210 KJ/m 2 , respectively).