This article explains the metal corrosion process including the basic chemistry of how metal loss occurs. Methods to control corrosion are also listed and explained. [Read more…]

Chemical corrosion occurs at increased rates in agitated conditions.

Typical iso-corrosion curves for alloy metals no longer apply. These curves only show corrosion rates at various chemical concentrations and temperatures in stagnant conditions.

A typical curve is shown below. The curves are available from alloy metal suppliers on request.

When metals are selected for agitated corrosive conditions the curves can only be used in a relative sense.

They help grade the metal selection but they cannot provide absolute corrosion rates. [Read more…]

Chemical corrosion can destroy the containment materials in contact with a process.

Means exist to mitigate and even prevent chemical corrosion. This article focuses on several such methods.

Acceptable corrosion

At times chemical corrosion is acceptable and one need only allow for it by using thicker materials. An example is the storage of sulphuric acid in mild steel tanks at ambient conditions and concentrations [Read more…]