Method and apparatus for measuring contact resistance for spot welding simulations

摘要

A method and apparatus for measuring the contact resistance at electrode-to-workpiece and workpiece-to-workpiece interfaces for spot welding simulations. A constant compressive load is applied through electrodes and workpieces to simulate a load applied during an actual resistance spot welding process. A discharging current circuit applies an initial high current of the order of 1.2 KA to electrodes and workpieces to break down contaminant films on surfaces of the workpieces. A relatively small constant current of about 2A is then applied to the electrodes and workpieces and the voltage across and the current flow through the electrodes and workpieces are measured. The contact resistance is determined from the measured voltage and current.