How do aluminum strips protect against corrosion?

Aluminum strips protect against corrosion through a process known as sacrificial anode cathodic protection. When aluminum is exposed to an electrolyte (like soil or water), it naturally forms a thin, protective oxide layer on its surface. This layer prevents further oxidation. In a galvanic cell, aluminum acts as the anode and corrodes preferentially, sacrificially protecting the cathode, which is usually a more noble metal like steel. The aluminum strip corrodes instead of the steel, thus preventing the steel from corroding. This method is effective because aluminum is more reactive than steel, and it corrodes at a slower rate once the initial protective layer is formed, making it a sustainable protection method.