An improved method to spot-weld difficult junctions

Recent advances in spot-welding technology such as high frequency direct cu rrent inverter welders provide an improved and reproducible method to spot- weld difficult junctions. The importance of removing the oxide layers on me tal surfaces, accurately delivering the weld pulse profile, and controlling the force applied to the materials during the welding process are discusse d in the context of resistance spot-welding a molybdenum crystal to a tanta lum loop and attaching a tungsten-rhenium thermocouple to the crystal. (C) 2001 American Institute of Physics.