1. Cathodic protection
Cathodic protection (CP) is a technique used to control the corrosion of a metal surface by making it the cathode of an electrochemical.
2. Sacrificial Anode
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.
3. Aluminium and Zinc Anode
An anode is an electrode through which the conventional current enters into a polarized electrical device. This contrasts with a cathode, an electrode through which conventional current leaves an electrical device. A common mnemonic is ACID for “anode current into device”  The direction of conventional current (the flow of positive charges) in a circuit is opposite to the direction of electron flow, so (negatively charged) electrons flow out the anode into the outside circuit. In a galvanic cell, the anode is the electrode at which the oxidation reactionoccurs.