Corrosion layer formation

Hatva, T. (1989) Iron and manganese in ground-water in Finland Occurrence of glacifluvial aquifers and removal by biofiltration. Publ. Water environmental research institute. Nat. Board Waters Envir., Finland, No. 4, 99 p. Haupt, S. Strehlow, H.H. (1987) Corrosion layer formation and oxide reduction of passive iron in alkaline solution A combined electrochemical and surface analytical study. Langmuir 3 837-885... 

In corrosion, adsorbates react directly with the substrate atoms to form new chemical species. The products may desorb from the surface (volatilization reaction) or may remain adsorbed in forming a corrosion layer. Corrosion reactions have many industrial applications, such as dry etching of semiconductor surfaces. An example of a volatilization reaction is the etching of Si by fluorine [43]. In this case, fluorine reacts with the Si surface to form SiF gas. Note that the crystallinity of the remaining surface is also severely disrupted by this reaction. An example of corrosion layer formation is the oxidation of Fe metal to form rust. In this case, none of the products are volatile, but the crystallinity of the surface is disrupted as the bulk oxide forms. Corrosion and etching reactions are discussed in more detail in section A3.10 and section C2.9. 

Processes During the Initial Stage of Corrosion Layer Formation... 

Haupt S, Strehblow H-H (1987) Corrosion, layer formation and oxide reduction of passive iron in alkaline solution, a combined electrochemical and surface analytical study. Langmuir 3 873-885. doi 10.1021/ Ia00078a003... 

D. G. Chen, C. J. Simmons, and J. H. Simmons, Corrosion layer formation of ZrF4-based fluoride glasses. Mater. Sci. Forum, 19-20 315-320,1987. 

Model of a passive layer with the related reactions of corrosion, layer formation, and complex formation. (From Strehblow, H.-H., in Passivity of Metals, R.C. Alkire, D.M. Kolb, eds.. Advances in Electrochemical Science and Engineering, Vol. 8, Wiley-VCH, Weinheim, Germany, pp. 271-374,2(X)3.)... 

The corrosion of metals and alloys generally starts at the surface with the formation of an outer layer, which may develop into a crust of corrosion products. If a crust is formed, it generally has a layered structure comprising two or more compounds (1) an outer, rather stable, mineralized layer that often covers entirely the surface of the objects, and underneath, (2) a less mineralized, unstable, and chemically active layer. Some corrosion layers may also bind ugly and disfiguring earthy accretions. 

Lead. Ancient lead objects excavated from the ground are often affected by ions in the groundwater and become covered by a white layer made up of a wide range of lead corrosion products (see Table 45). Sometimes, however, the early formation of a corrosion layer of cerussite (composed of lead carbonate), provides the metal with a protective coating that prevents the progress of the corrosion process. 

What are the factors that favor monolayer or multilayer passivation layer formation by a corrosion inhibitor on copper surface ... 

The final type of boundary layer results from chemical reactions of metal surfaces with the slurry chemicals. During metal CMP, the slurry chemicals react with the metal surface and form either solid or ionic products or both. Such reactions are considered corrosion reactions. Formation of solid species occurs on the metal surface, forming a surface layer which, to varying de-... 

An example of corrosion product formation is the rusting of iron as illustrated in Fig. 1.3. When the pH is greater than approximately 4, and under aerated conditions, a layer of black Fe304, and possibly Fe(OH)2, forms in contact with the iron substrate. In the presence of the dissolved oxygen, an outer layer of red Fe203 or FeOOH forms. The adherence... 

Through formation of the Pb02 corrosion layer, the electron-conductive surface of the plate increases and thus the current density is reduced and the cell voltage decreases. This allows an increase in the formation current to a higher value (to a rate of 0.2 C) for a certain period of time. The... 

Fig. 22 A classical diagram for the competition between layer formation (/ ) and corrosion (I corr = cl- The upper scale gives the overpotential at the oxide/electrolyte interface ijh- Measurements were carried out at various pH values at constant sulfate concentration [139].

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