Laboratory and production testing of novel resistance spot welding electrodes

The performance of two novel resistance spot welding electrodes was evaluated through the General Motors WS-5A laboratory test and production trials in an automotive assembly plant. The novel electrodes featured enhanced cooling properties such as a reduced face thickness and internal fins. The potential for a multiple-oxide dispersion strengthened copper electrode material is revealed given its performance in both the laboratory and production testing. For the production trials, extended electrode life and lower current levels were achieved compared to the baseline electrode. The results suggest that the optimum face thickness for electrode cooling is greater than 6 mm for a cooling-water flow rate of 0.5 gpm. The results also indicate that increased cooling-water flow rate is more beneficial for electrodes with cooling properties that enhance convective heat transfer. A methodology is presented for developing weld schedules in production operations.