How can cathodic protection be achieved?

Cathodic protection is primarily achieved through two methods: impressed current and galvanic anodes. Impressed current systems use a direct current from an outside power source to drive electrons to the protected metal surface, reducing the corrosion rate. This is highly effective for larger structures or in environments with high corrosion potential.

On the other hand, galvanic anodes are made from more reactive metals and are placed in electrical contact with the structure to be protected. They corrode preferentially, sacrificing themselves to protect the more valuable metal. Employing both of these methods allows for enhanced protection against corrosion, especially in various environmental conditions.

The other options, while related to corrosion protection, do not specifically address cathodic protection. Rectifiers and fuses relate to electrical circuit protection, insulating coatings are about barrier protection to prevent moisture contact, and sacrificial metals, while a significant part of galvanic protection, do not encompass the broader scope of cathodic protection that includes both galvanic and impressed current methods.