Method and apparatus for measuring contact resistance for spot welding simulations

An apparatus for measuring the electrical contact resistance at electrode-to-workpiece and workpiece-to-workpiece interfaces for resistance spot welding simulation comprising:

• loading means to apply compressive load through electrodes and workpieces to stimulate a load applied during resistance spot welding;
• heating means for heating the electrodes to maintain the electrodes and workpieces at a constant temperature;
• cooling means located beneath the electrodes to cool the electrodes and increase the temperature gradient;
• a discharging current circuit connected between the electrodes to provide a high current through the electrodes and workpieces to break down contaminant films on surfaces of the workpieces;
• and
• a small constant current source connected to the electrodes to supply a constant current flow through the electrodes and workpieces to allow the contact resistance of the electrodes and workpieces to be measured.