Sacrificial coating is a method of corrosion control by applying a thin layer of a metal having lower (than the protected metal) value of electrode potential (higher position in the table of Electrochemical series). The most common example of sacrificial coating is galvanized steel (steel coated with zinc).
Also asked, what is sacrificial protection?
Sacrificial protection is the protection of iron or steel against corrosion by using a more reactive metal. Pieces of zinc or magnesium alloy are attached to pump bodies and pipes. The protected metal becomes the cathode and does not corrode. The anode corrodes, thereby providing the desired sacrificial protection.
Furthermore, what’s the difference between Galvanising and sacrificial protection? In galvanisation, zinc is coated on the surface of iron to prevent it from corroding. But sacrificial protection is the process where zinc is kept near iron surface so that zinc corrodes instead of iron.
Consequently, what is cathodic protection and how does it work?
Cathodic protection prevents corrosion by converting all of the anodic (active) sites on the metal surface to cathodic (passive) sites by supplying electrical current (or free electrons) from an alternate source. Usually this takes the form of galvanic anodes, which are more active than steel.
What does sacrificial metal mean?
A sacrificial metal is a metal used as a sacrificial anode in cathodic protection that corrodes to prevent a primary metal from corrosion, galvanization or rusting.