Effects of Salt Atmosphere on Crack Sensitivity of Commercial Titanium Alloys at 600 to 900 F

Abstract

Creep tests were performed on titanium alloy tension specimens that had the gage length coated with salt. Three alloys, Ti-6A1-4V, Ti-8Al-lMo-lV, and Ti-2.5Al-lMo-10Sn-5Zr, were tested for 100 hr at temperatures above 600 F. Test results indicate: (1) all titanium alloys tested susceptible to stress corrosion, (2) salt causes cracking but does not cause catastrophic failure unless threshold stress is exceeded, (3) the degree of susceptibility is time dependent, and (4) degree of susceptibility decreases with decreasing aluminum content for temperatures above 600 F.