Which type of corrosion occurs between dissimilar metals in a corrosive environment?

Galvanic corrosion occurs when two dissimilar metals are in contact with each other while exposed to an electrolyte, such as a corrosive environment. In this process, one metal acts as the anode and the other as the cathode. The anode experiences corrosion and loses material, while the cathode is protected due to the flow of electrons from the anode to the cathode. This type of corrosion is driven by the electrochemical potential difference between the two metals, leading to accelerated deterioration of the less noble metal (the anode) in the presence of an electrolyte.

In contrast, concentration cell corrosion involves variations in ion concentration within a given environment affecting localized corrosion. Stress cell corrosion occurs when residual stresses in a material, often due to manufacturing or service conditions, lead to corrosion in specific areas. Uniform corrosion involves a consistent and even deterioration of material across its surface due to a uniform corrosive environment, without the influence of dissimilar metals. Each of these corrosion types has different mechanisms and causes, illustrating the specific nature of galvanic corrosion when dissimilar metals are involved.