If steel and brass pipe fittings are mixed, which will corrode away?

When steel and brass pipe fittings are mixed, the steel will corrode away faster due to a phenomenon known as galvanic corrosion. This occurs when two different metals are in contact in the presence of an electrical conductor, such as water. In this scenario, steel acts as the anode while brass, being the more noble metal, acts as the cathode.

The anode, which is the less noble metal (in this case, steel), will suffer from corrosion as electrons flow from it to the cathode (brass). Over time, this will lead to significant deterioration of the steel fittings while the brass fittings will maintain their integrity. Understanding the principles of galvanic corrosion is essential for those working with mixed-metal piping systems to ensure longevity and reliability in plumbing installations.