Corrosion protection

Corrosion protection describes targeted measures to prevent corrosive - i.e. decomposing - attacks on a metallic component.

The primary task of corrosion protection is to minimise the damage caused to the component by the action of corrosion. Since absolute corrosion resistance can never be achieved, the challenge is to ensure adequate protection for the service life of the component to be protected. The driving force of corrosion - i.e. the type and intensity - always depends on the oxidisability of the respective metal. This driving force is usually described by the so-called electrochemical potential of the metal. This means that in order to prevent corrosion, the electrochemical processes that favour it must be effectively avoided. In practice, there are two ways of doing this:

1. Active protection of the metal by increasing the electrochemical stability: This can be achieved, for example, by certain corrosion inhibitors. These special additives offer the possibility of chemically binding corrosive media such as oxygen, water and salt and thus slowing down the corrosion process.

2. Passive protection of the metal through coatings and (non-)metallic coatings (conversion layers): The so-called physical blocking - i.e. the separation between metal and environment by a layer applied to the component - provides protection against corrosive media.

Each of these corrosion protection measures can theoretically be applied on its own. Often, however, a combination of both concepts is indispensable for the best protection. Depending on the component and application area, there are numerous strategies for both active and passive corrosion prevention.