Skip to main content
A B C D E F H I K M N O P R S T V W
Ca Ch Cm Co Cr
Coa Com Con Cor

Corrosion mechanisms

Written by on .

Definition: Corrosion mechanisms describe the physico-chemical processes that lead to the degradation of a material through reaction with its environment. They are usually based on electrochemical redox reactions between metal, electrolyte and oxidising agent. The type and progression depend on the material, medium, temperature and mechanical loading.

Practical relevance: The most important mechanisms include uniform surface corrosion, pitting corrosion, crevice corrosion, galvanic corrosion, stress corrosion cracking (SCC) and hydrogen-induced cracking. Evaluation parameters are the corrosion rate (mm/year), potential differences, pH value and chloride content. Normative definitions can be found, among others, in DIN EN ISO 8044. Knowledge of the mechanism is a prerequisite for effective corrosion protection.

Decision-making perspectives:

  • Technical decision-makers: Selection of suitable materials, coatings or protection systems.
  • Purchasing/project management: Specification of corrosion-resistant materials and testing requirements.
  • Science: Analysis of electrochemical processes and material-medium interactions.
  • Insurance/law: Determining the cause of corrosion damage and assessing the duty of care.

Typical testing or verification methods: Electrochemical measurements, salt spray test, metallography, wall thickness measurement (UT).

FAQ:

  • Why is identifying the corrosion mechanism important?
  • Only by knowing the mechanism can suitable protection and prevention measures be defined.
Request analysis →