Prediction of VT18U titanium alloy fatigue life at elevated temperatures with regard to surface machining process

We have suggested mathematical relations and an engineering technique for c alculating fatigue life in the multicycle area at standard and elevated tem peratures. The influence of quality parameters of a part surface layer (har dness, residual stresses and surface roughness) has been taken into account in connection with its manufacture practice. The calculations are confirme d by experimental data for parts made of the titanium alloy VT18U after vib ropolishing, hardening by microballs, nitrogen ion implantation.