Page 184 - Corrosion Engineering Principles and Practice

158 C h a p t e r 6 R e c o g n i z i n g t h e F o r m s o f C o r r o s i o n 159

Cu(OH) (SO ) Blue
x
4 y
and
CuCO Cu(OH) Green
2
3

Copper
pipe wall
Cuprous oxide (Cu O) layer
2

FIGURE 6.13 Type II copper pitting corrosion. (Courtesy of Russ Green, TMI)

Typically, a local cell will lead to the initiation of a pit due to the
presence of an abnormal anodic site surrounded by normal surface
which acts as a cathode, or by the presence of an abnormal cathodic
site surrounded by a normal surface in which a pit will have

Cu(OH) (SO ) Blue
x
4 y

Cuprous oxide (Cu O) layer
2

Copper
pipe wall

FIGURE 6.14 Type III copper pitting corrosion. (Courtesy of Russ Green, TMI)