The base of the problem in liquid cooling is when you mix copper or nickel plated copper with aluminum parts, where the aluminum is the much more active material. But, galvanic corrosion does not occur only with liquid cooling loops, one example is when you connect aluminum frames with steel screws. In a humid environment, the steel screws will drive the corrosion of the aluminum which is much more active. Also, if you are using aluminum pop-rivets on steel parts, expect the rivets to give up after a while, especially if it’s exposed to humidity and rain. The issues of mixing different types of metals are very precisely documented in the engineering textbooks , it’s kind of important to point out that the occurrence of galvanic corrosion is not a new thing invited by liquid cooling enthusiasts.

When the two types of metal are in contact with each other and are covered with an electrolyte (water), then the more active metal (like aluminum) becomes anodic, and the passive metal cathodic. It is always the anode, the less noble material that corrodes and dissolves into the electrolyte. The electric potential difference between various types of metals is what drives the accelerated corrosion as a flow of electrons from the anode to the cathode. The bigger the cathode area is in relation to the anode, the faster the active metal will corrode. This same galvanic reaction is used in batteries to generate potential difference (voltage), or should we say electricity. Low-cost batteries typically contain carbon-zinc cells. The zinc inside the battery cell will corrode as it is an essential process of the battery producing electricity. By reading this far into the article, you are quite aware that having aluminum or zinc in your regular copper or nickel plated liquid cooling loop is not a good idea. Do you want to see how does galvanic corrosion look like?