Which method is used in cathodic protection to eliminate corrosion?

The method that is used in cathodic protection to eliminate corrosion is through making the structure a cathode. In cathodic protection, the goal is to prevent corrosion by changing the electrochemical environment of the metal surface. When a structure, such as a pipeline or steel structure, is made a cathode, it means that it gains electrons and undergoes a reduction reaction, which counteracts the corrosive oxidation reaction occurring on the surface. By doing this, the corrosion potential is shifted, and the corrosion rate is significantly reduced or even eliminated.

This approach is effective because it disrupts the natural galvanic cell process that leads to corrosion, making the metal less susceptible to rusting or deterioration. By either connecting the structure to a more sacrificial anode (as in galvanic cathodic protection) or using impressed current systems to introduce external currents, the structure becomes protected against corrosion.

Understanding why making the structure a cathode is effective in combating corrosion highlights the fundamental principles of electrochemistry that are critical in coatings and corrosion control within the coatings inspection field. Other methods like enhancing surface coatings, using galvanic inhibitors, or increasing thermal resistance may contribute to reducing corrosion, but they do not operate on the same electrochemical principles as cathod