Search Results for atmospheric corrosion

This article discusses the elements necessary for a galvanic cell operation. Detailed information on the possible corrosion reaction as a function of aqueous electrolyte concentration and pH, in the presence of certain ions, are provided using Pourbaix diagrams. A variety of atmospheric factors, climatic conditions, and air-chemical pollutants that determine the corrosiveness of the atmosphere and contribute to the metal corrosion process are discussed. The article reviews the phenomenon of precipitation runoff on the corroded metal surface and the corrosive microbial effect on metals. It describes the thermodynamics of atmospheric corrosion and models for predicting the corrosion damage of metals. The article concludes with information on the various trends in atmospheric corrosion research and methods for the corrosion processes.

This article provides a general technical description of thermal spray coatings used for corrosion protection in atmospheric and aqueous environments. It further discusses two basic coating approaches of corrosion protection, namely, the sacrificial coating of thermal spray aluminum (TSA) and thermal spray zinc (TSZ), and the barrier-type coating of corrosion-resistant materials. The emphasis is on sacrificial coatings. The article describes the steps involved in the application of TSA and TSZ: surface preparation, coating deposition, and postspray treatment. It discusses their field exposure tests and application history. The article also contains helpful information on the dense barrier coatings by high-velocity spraying processes along with their corrosion performance.

Several factors contribute to marine-atmospheric corrosion with the local environment being the single most important factor. Therefore, assessing a local environment, which is essential to reduce the gross expenditure, is assisted by modeling of the local environment and by a set of corrosion standards proposed by the International Standards Organization (ISO). This article focuses on the important variables associated with atmospheric corrosion in marine atmospheres, namely, moisture, temperature, winds, airborne contaminants, alloy content, location, and biological organisms along with their corresponding assessing methods. It also examines the ISO CORRAG program for modeling the corrosion rate of atmospheric corrosion that is represented as equations modeling.