55-45 alloy was perforated by crevice corrosion after 1064 days of 

 exposure at the 6,000 foot depth. 



Copper-nickel alloys 95-5, 90-10, 80-20, 70-30 containing 0.5 per- 

 cent and 5 percent iron were not susceptible to stress corrosion crack- 

 ing at either depth in the Pacific Ocean. 



The mechanical properties of 95-5, 90-10, 80-20, 70-30 containing 

 0.5 percent iron and 70-30 containing 5 percent iron copper-nickel 

 alloys were not adversely affected by exposure at either depth in the 

 Pacific Ocean. 



Corrosion products on 70-30 copper-nickel alloy containing 5 per- 

 cent iron were nickel hydroxide (Ni(0H)2), cupric chloride (CUCI2) and 

 copper metal, 44 percent. 



Because of the selective corrosion of the majority of the copper- 

 zinc alloys, the aluminum bronzes, nickel-aluminum bronze containing 

 10 percent aluminum and the silicon brzones, they would be unsatis- 

 factory for use in sea water applications, especially for long periods 

 of constant immersion at depth. 



Copper, beryllium-copper, arsenical admiralty brass, aluminum 

 brass, nickel brass, the bronzes except the aluminum bronzes, nickel- 

 aluminum bronze containing 10 percent aluminum and the silicon bronzes, 

 and the nickel-copper alloys would be satisfactory for deep submergence 

 applications because of their low corrosion rates, uniform type of 

 corrosion, non-susceptibility to stress corrosion cracking, and no ad- 

 verse effect on their mechanical properties. 



REFERENCES 



1. U. S. Naval Civil Engineering Laboratory Technical Note N-900: 

 Corrosion of Materials in Hydrospace - Part I. Irons, Steels, Cast 

 Irons and Steel Products, by Fred M. Reinhart. Port Hueneme , Calif., 

 July 1967. 



2. . Technical Report R-504: Corrosion of Materials in 



Hydrospace, by Fred M. Reinhart. Port Hueneme, Calif., Dec 1966. 



3. , Technical Note N-915: Corrosion of Materials in 



Hydrospace - Part II. Nickel and Nickel Alloys, by Fred M. Reinhart. 

 Port Hueneme, Calif., Aug 1967. 



4. . Technical Note N-921: Corrosion of Materials in 



Hydrospace - Part III. Titanium and Titanium Alloys, by Fred M. Reinhart. 

 Port Hueneme, Calif., Sep 1967. 



5. . Technical Note N-605: Preliminary Examination of 



Materials Exposed on STU 1-3 in the Deep Ocean - (5,640 Feet of Depth 

 for 123 Days), by Fred M. Reinhart. Port Hueneme, Calif., Jun 1964. 



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