Arcs and sparks are commonly used to dramatically depict welding in television commercials, photographs and other images. But in resistance projection welding (RPW), such flashes of light indicate poor welding.

When the average person opens up a refrigerator and grabs a too-warm soda can or bottle, his initial reaction is one of disappointment. But, if that person is an assembler of harnesses for this type of appliance, his initial thought is: Check the evaporator fan wiring harness.

WARREN, MI—General Motors engineers have developed a technique to join steel to aluminum with resistance spot welding.

Established methods—like ultrasonic and resistance welding—increasingly face competition from advancing technologies like laser, friction and micro welding.

Weld nuts are installed on steel plates or sheets to provide firm, fixed threads for a mating screw or bolt.