From Corrosion Properties of Materials

Electrochemistry of Corrosion

Corrosion is most visible when the corrosive substance is moisture or water. When the metal surface is exposed to water or moisture, it reacts with the water in a process called oxidation, which means the reaction of a substance with Oxygen. This reaction produces electrons in the metal while a reduction reaction consumes electrons. Together, they form a Corrosion Cell.


A reduction reaction consumes the electrons produced by an anodic reaction.

During an oxidation reaction, the metal dissolves to form a soluble metal compound or an insoluble oxide depending on environmental conditions. In the oxidation reaction, the flow of electrons is necessary for the completion of the corrosion reaction.

An example of a typical anodic oxidation reaction that occurs on a metal surface in a "Corrosion Cell" is:

Fe ==> Fe 2+ + 2e

An example of a cathodic reduction is:

O 2 + 2H 2O + 4e - ==> 4OH

Products & Services
Surface and Corrosion Protection Products
Surface protection products and corrosion protection products are used to provide protection to industrial surfaces particularly in the marine, transportation, chemical process, pulp and paper, and petroleum industries.
Rust and Corrosion Inhibiting Fluids
Rust preventives and corrosion inhibitors are lubricants, greases, oils or fluid additives that form a protective film or barrier to prevent corrosion or rust formation.
Inhibitors and Stabilizers
Inhibitors suppress, decrease, or prevent a reaction from occurring while stabilizers are used to maintain specific functions or properties of a product or additive.
Oxidation Reduction Potential (ORP) Electrodes
Oxygen reduction potential (ORP) electrodes are analytical sensors for measuring oxidation-reduction potential (ORP).

Topics of Interest

Effect of Corrosion Corrosion affects all metals at large, and that effect is quite visible in most cases. For example, in case of corrosion on a Tin surface, whiskers grow on the surface. In the...

CORROSION, PASSIVATION, AND IMMUNITY Electrochemical Reactions Metal species can be released into water either from the simple dissolution of existing scale materials, or actual electrochemical...

4.3.8 METHODS OF PREVENTION OF GALVANIC CORROSION Select metals, close together, as far as possible, in the galvanic series. Do not have the area of the more active metal smaller than the area of...

5.1 INTRODUCTION Cathodic protection is a proven corrosion control method for protection of underground and undersea metallic structures, such as oil and gas pipelines, cables, utility lines and...

OVERVIEW For corrosion to take place, the formation of a corrosion cell is essential. A corrosion cell is essentially comprised of the following four components (Fig. 2.1). Anode Cathode...