Engine coolants corrosion mechanism

There are many corrosion mechanisms which can take place in today s engines. The complexity has increased with the use of aluminum alloys in the head and block. Aluminum used in areas such as the head, where large quantities of heat are liberated to the coolant, is subject to a unique heat rejection corrosion. To protect against the heat rejection corrosion of aluminum, a coolant having special corrosion inhibitor systems must be used. 

The primary function of a lubricant is to create a film barrier between moving mechanical parts to reduce friction and wear. It also acts as a coolant, suppresses harmful deposit formation and controls corrosion/oxidation. Since the base oil alone would struggle to meet these challenging demands, performance-enhancing additives in tailor-made formulations are added to the lubricant formulation. These packages can include antioxidant, antiwear, corrosion inhibitor, viscosity modifier, detergent and dispersant components. Not only do these additives improve overall efficiency in the engine, but they also extend the lifetime of the lubricant. 

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