ESDU 83012 presents graphically as stress versus endurance curves (S-N curves) the results of some 500 constant amplitude fatigue tests on titanium alloy screw threads to provide fatigue strengths at room temperature, at elevated temperature and at room temperature after soaking at elevated temperature. The titanium alloys covered are Ti-4Al-4Mn, Ti-5Al-3Mn, Ti-6Al-4V, Ti-6Al-6V-2Sn and Ti-7Al-12Zr plus a limited amount of data on Ti-8Al-1Mo-1V. The thread forms included UNF, ISO metric, BSF and BA. Some data on the effects of zinc plating or anodising the Ti-4Al-4Mn threads are included.