CORROSION

Corrosion removal deals with the taking away of mass from the surface of materials by their environment and other forms of environmental attack that weaken or otherwise degrade material properties. The complex nature of corrosion suggests that the designer who is seriously concerned about corrosion review a good readable text such as Corrosion Engineering by Fontana and Greene [35.1].
Included in this chapter are many corrosion data for selected environments and materials. It is always hazardous to select one material in preference to another based only on published data because of inconsistencies in measuring corrosion, lack of completeness in documenting environments, variations in test methods, and possible publishing errors.These data do not generally indicate how small variations in temperature or corrosive concentrations might drastically increase or decrease corrosion rates. Furthermore, they do not account for the influence of other associated materials or how combinations of attack mechanisms may drastically alter a given material’s behavior. Stray electric currents should be considered along with the various attack mechanisms included in this chapter. Brevity has required simplification and the exclusion of some phenomena and data which may be important in some applications.
The data included in this chapter are but a fraction of those available. Corrosion Guide by Rabald [35.2] can be a valuable resource because of its extensive coverage of environments and materials.
Again, all corrosion data included in this chapter or published elsewhere should be used only as a guide for weeding out unsuitable materials or selecting potentially acceptable candidates. Verification of suitability should be based on actual experience or laboratory experimentation. The inclusion or exclusion of data in this chapter should not be interpreted as an endorsement or rejection of any material.

Milton G. Wille, Ph.D., P.E.
Professor of Mechanical Engineering
Brigham Young University
Provo, Utah

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