Engineers at Ohio State University have developed a welding technique that they say consumes 80% less energy than common welding methods, yet creates bonds that are 50% stronger.

The development could have significant impact for automakers, offering them greater liberty to design vehicles that combine traditional heavy steel parts with lighter, alternative metals to reduce vehicle weight.

Over the last decade, Glenn Daehn, professor of materials science and engineering at Ohio State, and his team have amassed more than half a dozen patents on a system called vaporized foil actuator (VFA) welding. In VFA, a high-voltage capacitor bank creates a short electrical pulse inside a thin piece of aluminum foil. Within microseconds (millionths of a second), the foil vaporizes and a burst of hot gas pushes two pieces of metal together.

The pieces do not melt so there is no seam of weakened metal between them. Instead, the impact bonds the atoms of one metal to atoms of the other.

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.

That contrasts with the commonly used technique known as resistance spot welding, in which welders pass a high electrical current through pieces of metal so that the metals’ natural electrical resistance generates heat that partially melts them together and forms a weld. The drawbacks are that generating high currents consumes a lot of energy, and the melted portions of metal are seldom as strong afterward as they were before.

So far, the Ohio State engineers have successfully bonded different combinations of copper, aluminum, magnesium, iron, nickel and titanium. They have created bonds between commercial steel and aluminum alloys—a feat that they say is unattainable using spot welding. Also, high-strength steel and aluminum join together with weld regions that are stronger than the base metals.

The technique is powerful enough to shape metal parts at the same time it welds them together, saving manufacturers a step.

The research is funded by the U.S. Department of Energy and the National Science Foundation. Daehn and his team now want to join with manufacturers to further develop the technology, which will be licensed through Ohio State’s Technology Commercialization Office.