The process of making bi-metallic lugs revolves around a technique known as friction welding, which is fantastic for joining different metals like aluminum and copper. Here’s how it works: the aluminum barrel and copper palm are carefully prepared and machined to fit perfectly. One part, usually the aluminum, spins at a high speed while the copper piece stays still. As these two surfaces press against each other with controlled pressure, the friction creates heat right at the contact point. This heat softens the metals without melting them, allowing them to bond at a molecular level. Once everything reaches the right temperature and pressure, the spinning stops, and more pressure is applied, creating a strong, seamless joint between the two metals.
This solid-state welding technique is favored because it sidesteps the melting and mixing problems that can happen with traditional fusion welding, which is crucial given the different melting points and oxidation behaviors of copper and aluminum. The end result is a robust and corrosion-resistant connection, perfect for electrical applications. Companies like Pioneer Power International use friction welding to create bi-metallic lugs that ensure reliable performance, providing safe and long-lasting connections in power distribution systems.