Electron-Beam Technology in Switch Contacts

The original concept was to develop a composite strip of material for switch contacts, such that the silver portion is suitably bonded to the base metal such as copper, phosphor bronze, or beryllium copper. The requirements were a metallurgically sound reproducible-nonporous uniform ductile bond. Electron-beam welding technology meets these requirements for joining switch contact materials. Fine silver, coin silver, silver cadmium oxide, and other wrought contact materials can be continuously electron-beam welded to the base metal switchblade member and then subsequently stamped and formed to the necessary switch configuration. This manufacturing technique is an improvement over the alternate joining methods of resistance welding, brazing, tungsten inert gas welding, thermocompression bonding, and the more recent laser welding.