xv
List of Figures
Figure 2.1 Salt concentration cell ....................................................................9
Figure 2.2 Differential aeration cell .............................................................. 10
Figure 2.3 Potential–pH (Pourbaix) diagram for Fe–H 2 O system ............12
Figure 2.4 Polarization of iron in acid ..........................................................15
Figure 2.5 Steps involved in hydrogen reduction reaction ....................... 16
Figure 2.6 Activation polarization curve of a hydrogen electrode ..........17
Figure 2.7 (a) Concentration polarization curve for reduction
process, and (b) effect of environmental variations on concentration
polarization curve ................................................................................................18
Figure 2.8 Combined curve of activation and concentration
polarizations for reduction process ...................................................................19
Figure 2.9 Anode polarization measurement apparatus ..........................20
Figure 2.10 Anodic and cathodic polarization curve ..................................20
Figure 2.11 Anodic polarization curve for material exhibiting activepassive behavior ...................................................................................................21
Figure 2.12 Schematic representation of a material with activepassive behavior in different corrosive environments ...................................22
Figure 2.13 Effects of environment and alloy content on anodic
polarization behavior ..........................................................................................23
Figure 2.14 Increased corrodent velocity can shift the cathodic
polarization curve such that passive behavior can be induced ....................24
Figure 3.1 Effect of carbon content on carbide precipitation. Carbide
precipitation forms in the areas to the right of the various carbon
content curves .......................................................................................................33
Figure 3.2 Formation of pit from break in mill scale .................................42
Figure 3.3 Loss of ductility in steel as a function of hydrogen content ..60
Figure 3.4 Schematic of safe operating limits for steel in hydrogen .......64
Figure 4.1 Schematic illustration of processes occurring in or at the
aqueous layer ........................................................................................................95
List of Figures
Figure 2.1 Salt concentration cell ....................................................................9
Figure 2.2 Differential aeration cell .............................................................. 10
Figure 2.3 Potential–pH (Pourbaix) diagram for Fe–H 2 O system ............12
Figure 2.4 Polarization of iron in acid ..........................................................15
Figure 2.5 Steps involved in hydrogen reduction reaction ....................... 16
Figure 2.6 Activation polarization curve of a hydrogen electrode ..........17
Figure 2.7 (a) Concentration polarization curve for reduction
process, and (b) effect of environmental variations on concentration
polarization curve ................................................................................................18
Figure 2.8 Combined curve of activation and concentration
polarizations for reduction process ...................................................................19
Figure 2.9 Anode polarization measurement apparatus ..........................20
Figure 2.10 Anodic and cathodic polarization curve ..................................20
Figure 2.11 Anodic polarization curve for material exhibiting activepassive behavior ...................................................................................................21
Figure 2.12 Schematic representation of a material with activepassive behavior in different corrosive environments ...................................22
Figure 2.13 Effects of environment and alloy content on anodic
polarization behavior ..........................................................................................23
Figure 2.14 Increased corrodent velocity can shift the cathodic
polarization curve such that passive behavior can be induced ....................24
Figure 3.1 Effect of carbon content on carbide precipitation. Carbide
precipitation forms in the areas to the right of the various carbon
content curves .......................................................................................................33
Figure 3.2 Formation of pit from break in mill scale .................................42
Figure 3.3 Loss of ductility in steel as a function of hydrogen content ..60
Figure 3.4 Schematic of safe operating limits for steel in hydrogen .......64
Figure 4.1 Schematic illustration of processes occurring in or at the
aqueous layer ........................................................................................................95