Definition - What does Cathodic Method mean?
The cathodic method is a technique used to mitigate corrosion on metal surfaces by transforming it to the cathode within an electrochemical cell. This method is commonly used to offer protection to storage tanks, fuel or water pipelines, ships as well as oil platforms and casings. It is the most effective solution to fight the damaging effects of stress corrosion cracking (SCC).
The cathodic method is also known as cathodic protection.
Corrosionpedia explains Cathodic Method
The cathodic method is a technique used to protect metal structures from the harmful effects of corrosion. It works by making the metal act as the cathode in electrochemical reaction. The protection is obtained by joining the metal to another metal that corrodes more easily, making it the anode in the reaction.
There are two types of cathodic protection:
- Galvanic or sacrificial - This type makes use of anodes that have elevated electrochemical potential compared to the structures to be protected. The structure surface potential undergoes polarization, leading to uniform potential, which puts off the process of corrosion. It is not practical for long-term and wide-scale corrosion protection.
- Impressed current - This involves the use of external DC delivered by longer-lasting anodes. The anodes are installed through groupings in an underground setting known as ground beds. One advantage of this type of cathodic method is that it offers longer life and limitless current opportunities.
With this type of protection, industries are able to establish safe and effective corrosion control.