Electronegative potential . A potential corresponding in sign to those 

 of the active or anodic members of the e.m.f. series. Because of the 

 existing confusion of sign in the literature, it is suggested that 

 "anodic potential" "be used whenever "electronegative potential" is 

 implied. (See Electromotive force series.) 



Electroosmosis . The flow of a liquid in the soil solution or membrane 

 because of difference in electrical potential on the two sides of the 

 membrane. As a result, the soil dries out at or near the anode, causing 

 an increase in soil resistivity. The principle has been used to migrate 

 considerable volumes of water to dry out and stabilize soil during 

 construction. 



Electropositive potential . A potential corresponding in sign to poten- 

 tials of the noble or cathodic members of the e.m.f. series. It is 

 suggested that "cathodic potential" be used whenever "electropositive 

 potential" is implied. (See e.m.f. series.) 



Embrittlement . Severe loss of ductility of a metal or alloy. 



Erosion . Destruction of a metal or other material by the abrasive action 

 of liquid or gas, usually accelerated by the presence of solid particles 

 of matter in suspension* and sometimes accelerated by corrosion. 



Exfoliation . Scaling off a surface in flakes or layers is termed 

 exfoliation. 



Film . A thin, not necessarily visible, layer of material. 



Fogged metal . A metal the luster of which has been sharply reduced by 

 a film of corrosion products is termed fogged metal. 



Fretting corrosion . Corrosion at the interface between two contacting 

 surfaces, accelerated by relative vibration between them of an amplitude 

 that is high enough to produce slip. 



Galvanic cell . A cell consisting of two dissimilar conductors in contact 

 with an electrolyte, or two similar conductors in contact with dissimilar 

 electrolytes. More generally a galvanic cell converts energy liberated 

 by a spontaneous chemical reaction directly into electrical energy. 



Galvanic corrosion . Corrosion associated with the electric current of a 

 galvanic cell that consists of dissimilar electrodes. It is also known 

 as couple action. 



Galvanic series . A list of metals and alloys arranged according to their 

 relative potentials in a given environment. 



Graphitization (graphitic corrosion) . Corrosion of gray cast iron in 

 which the metallic iron constituent is converted into corrosion products, 

 leaving the graphite intact. 



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