Corrosion of Materials in Hydrospace. Part III. Titanium and Titanium Alloys

摘要

A total of 475 specimens of 10 titanium alloys were exposed at two different depths in the Pacific Ocean for six different periods of time varying from 123 to 1064 days to determine the effects of deep ocean environments on their corrosion resistance. Specimens of the alloys were also exposed in surface seawater for 181 days for comparison purposes. Corrosion rates, types of corrosion, pit depths, effects of welding, stress corrosion cracking resistance and changes in mechanical properties are presented. The alloys were immune to corrosion and stress corrosion cracking except alloy 13V-11Cr-3Al. This alloy with unrelieved circular welds failed by stress corrosion cracking after 181 days of exposure at the surface, 403 days at 6,780 feet and 402 days at 2,370 feet. The 13V-11Cr-3Al alloy with unrelieved butt welds failed by stress corrosion cracking when stressed at 75 percent of its yield strength after 35, 77 and 105 days of exposure at the surface. The mechanical properties of the alloys were not affected. Some information for TOTO in the Atlantic Ocean is included for comparative purposes. (Author)