Difference between Zinc and Aluminum anodes When it comes to protecting metal structures from corrosion in marine environments, selecting the appropriate sacrificial anode is crucial. Zinc and aluminum anodes are two commonly used options, each with distinct properties and advantages. Composition and Properties Zinc Anodes: Traditionally known as "zincs," these anodes have been the standard for many years. They are effective in saltwater environments but may become less efficient in brackish or freshwater due to passivation—a process where a protective oxide layer forms, reducing their effectiveness. Aluminum Anodes: Composed of aluminum alloys, these anodes are lighter and have a higher electrochemical capacity compared to zinc. They perform well in both saltwater and brackish water, offering versatility across different marine environments. Performance and Efficiency Zinc Anodes: Provide reliable protection in saltwater but are less effective i...