A corrosion test is a type of materials test in which the goal is to determine a material's sensitivity to chemical reactions that might cause damage. In corrosion testing, a material is subjected to simulated conditions and then carefully analyzed for signs of cracking, fatigue, pitting, and other damage. This type of testing is offered by many materials testing laboratories and the cost vary depending on the material being tested and the types of tests that are administered.
Corrosion leads to rust, cracking, pitting, splitting, and a variety of other forms of damage. On a low level, corrosion can cause an aesthetic problem, but it can also seriously compromise a material and cause it to fail. Corroded fittings can become a safety risk or interfere with the efficiency of an operation. For this reason, companies are very careful about how they design and manufacture products, in order to limit the possibility of corrosion damage that might take a piece of equipment out of service before the end of its expected lifetime.
The type of test used depends on the material and the needs. Things like components for space shuttles are tested very rigorously, for example, because there is a very low tolerance for error in any of the parts. On the other hand, fittings for garden hoses do not require such meticulous testing. When objects are sent out for testing, the lab can make recommendations for a corrosion test based on the material and how it will be used.
In a basic corrosion test, the material is subjected to a corrosive material, such as saltwater, and then observed. Scientific instruments are used to monitor the ongoing chemical reactions that occur during the corrosion test. The testing facility takes note of the point when corrosion starts to set in and how quickly a component is rendered useless by corrosion. Some companies also offer corrosion stress testing such as boiling in manganese to determine when materials crack under stress.
Companies developing new coatings, materials, and components use corrosion testing to determine whether or not their products will meet the needs for which they are designed. In addition, laboratory corrosion testing can be used for quality control, in accident reconstructions where the goal is to determine whether corrosion was natural or induced, and in other settings when people want to learn more about materials. The corrosion test process is destructive in nature and cannot be used for materials and components that need to be left intact at the end of testing.