UNCLASSIFIED 



il v Clussifi. 



DOCUMENT CONTROL DATA -R&D 



. I.^silicatioti ol Kilo, holly ■•' .'h-.lr.n-l .i/i.J ,::,!■■ 



vd i-lu-n the iverall 



Naval Civil Engineering Laboratory 

 Port Hueneme , California 



Unclassified 



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



i (Type ol report and inch, 



Au THOHISI (First name, middle initial, la 



REINHART, Fred M. 



Au gust 1967 



30 



JJ^ 



b. PROJ EC T NO. 



Y-F015-01-05-002a 



Technical Note N-921 



■ (Any other numbers tha 



Each transmiHr£il of th^s^document o*rfsidi the agencLse-o-f~) the U. S^^government 

 must h^vepriyor apjMfoval of the^faval Cpil Engineering ^aboraj^erfy . 



Naval Facilities Engineering Command 

 Washington, D. C. 



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-llCr-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-llCr-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 from TOTO in the Atlantic Ocean is included for comparative 

 purposes . 



DD 



1473 



UNCLASSIFIED 



S/N 010 I • 807- 680 1 



