Explore the potential of capacitor-discharge welding

Capacitor-discharge welding (CDW) is a rapid-solidification joining process that the US Bureau of Mines developed to create welds having nonequilibrium microstructures. CDW produces high-reliability joints with no intermetallic compounds that can make them brittle, or trapped gases that can make them porous. It has the potential to be low in cost, and can easily be automated. One of the constraints on CDW is the finite amount of energy that can be stored in the capacitor, which limits total weld area. For this reason, CDW has been restricted to joining small solid cylinders to plates. However, research using 50 to 150 volts and 10[sup 4] to 10[sup 5] amperes has produced welds up to 13 mm (0.5 in.) in diameter. In one such experiment, titanium rods were successfully joined by using a cup-and-cone electrode geometry (pointed cathode and matching indented anode). The Bureau has welded a variety of dissimilar metals using the CDW process.