Abstract: According to the invention a hollow cylindrical shank of electrically conducting metal is connected to a resistance welder. A coolant supply tube passes through the shank and has an interior coolant supply passage. The coolant supply tube has an outer diameter less than the inner diameter of the hollow cylindrical shank. A weld cap seats on the shank and has a cap tip and a cap skirt that depends from the cap tip and is attached to the shank. An underside of the cap tip faces the shank and the supply tube. A coolant receiving bore formed into the underside of the weld cap extends into the cap tip to receive the coolant supply tube part way into the bore. The bore formed into the underside of the cap tip defines a bore sidewall that provides added area of heat transfer contact between the coolant and the cap tip.

Abstract: The present invention is directed to an improved laminated, sound damping resistance weldable composite and a method for its manufacture. The metal composite structure (10) features two metal members (12)(14) sandwiching a viscoelastic layer (26) where the viscoelastic layer entrains electrically conductive particles (28). Barrier elements (32) (34) are disposed between the metal members and the viscoelastic layer to inhibit and/or prevent contaminant migration into the metal from the viscoelastic layer and/or conductive particles during welding.