SUMMARY
Interrelation of strength, ductility and mechanical stability of structural titanium alloys is considered. It is ascertained that equation relating ductility () and strength () at the constant mechanical stability are parabolic by their behavior. They may be separated by the kind of their critical points – dependences with maximum or dependences with minimum. Ductility and strength of structural titanium alloys with different value to resist embrittlement at constant mechanical stability were optimized. Generalized diagram “ductility – strength – mechanical stability” was built. Equations describing structure and properties were obtained. Ranges of optimal combination of ductility and mechanical stability, which characterizes the metal of the best quality, were determined for high-strength and medium-strength titanium alloys. It is exhibited that accuracy of analysis of examined population of structural titanium alloys may differ from the those for the supposed whole population by the value that doesn’t exceed 4,5 %.