Engineers at The Ohio State University have developed a new welding technique that consumes 80 percent less energy than a common welding technique, yet creates bonds that are 50 percent stronger. The new technique could have a huge impact on the auto industry. Despite recent advances in materials design, alternative metals still pose a challenge to manufacturers. Many are considered un-weldable by traditional means, in part because high heat and re-solidification weaken them.

Microscope view of steel (top) welded to aluminum alloy (bottom) using VFA welding. (Image: Glenn Daehn)

In the new technique, called vaporized foil actuator (VFA) welding, a high-voltage capacitor bank creates a very short electrical pulse inside a thin piece of aluminum foil. Within microseconds, the foil vaporizes, and a burst of hot gas pushes two pieces of metal together at speeds approaching thousands of miles per hour. The pieces don’t melt, so there’s no seam of weakened metal between them.

The technique uses less energy because the electrical pulse is so short, and because the energy required to vaporize the foil is less than what would be required to melt the metal parts.