Creep 



Mechanical failure 

 Physical deterioration 

 Chemical deterioration 

 Biological deterioration 

 Electrochemical deterioration 

 Volume change 

 Water absorption 



Laboratory-Simulated Environments 



One of the early objectives of this task has been the investigation 

 of means of reproducing the deep=sea environment in the laboratory under 

 controlled conditions o Toward this end the literature has been studied 

 to determine the state of the art in this f ieldo Visits have been made 

 to various government^ university^ and industrial laboratories throughout 

 the country to examine high-pressure research facilities and to determine 

 what work has been done on this problemo As an outgrowth of these searches, 

 which disclosed a lack of the desired facilities, various high-pressure 

 laboratory vessels and facilities have been designed and are being 

 fabricated. 



NCEL's high-pressure laboratory, which will be described in detail 

 later in this report, will, when fully developed, be used to reproduce 

 the following aspects of the deep-ocean environment ; 



Hydrostatic pressxrre to 20,000 psi 



Temperature down to 0°C 



Sea-water chemistry as found in situ at great depth 



Shallow-Water Environments 



In order to study the differences in deterioration processes and 

 rates of deterioration in deep and in shallow water and to determine 

 if observed differences are in fact due to the environmental differences 

 and not differences in specimens or experimental technique, it may be 

 necessary to expose duplicate specimens of certain of the materials 

 under study in both environments for similar periods of time. Because 

 of its proximity. Port Hueneme Harbor has, for some years, been used as 

 a site for corrosion and protective coating studies by KCEL. The harbor 

 waters are relatively unpolluted and are monitored weekly for pH, salinity, 

 and solid content. 



Specimens exposed in this environment would be prepared from the 

 same lots of material used in the deep-water tests. The essential 

 difference in the exposure conditions, other than the environment. 



