The Akron Legal News

OSU researchers create stronger welding technique

ALLISON SLONAKER
Special to the Legal News
Published: December 1, 2015

A new welding technique created by engineers at The Ohio State University could have major impact on the auto industry.

The new technique consumes 80 percent less energy than common welding techniques, but the bonds created are 50 percent stronger, according to school researchers.

Despite advances in the design of materials, manufacturers still face challenges when working with alternative metals.

High heat and resolidification weaken the metals, so they are then considered unweldable by traditional means, said Glenn Daehn, professor of materials science and engineering at OSU, who also helped develop the new technique.

“Materials have gotten stronger, but welds haven’t. We can design metals with intricate microstructures, but we destroy the microstructure when we weld,” Daehn said.

“With our method, materials are shaped and bonded together at the same time and they actually get stronger,” Daehn said.

Daehn and his team have worked the past decade trying to find ways around the drawbacks in the common techniques. The team has created more than half a dozen patents on the system called vaporized foil actuator welding.

In vaporized foil actuator welding, very short electrical pulses are created by a high-voltage capacitor inside a thin piece of aluminum foil. The foil then vaporizes within microseconds and a burst of hot gas then pushes two pieces of metal together at speeds close to thousands of miles per hour.

With this method, the pieces are not melted so there isn’t a seam of weakened metal between them. The impact instead directly bonds the atoms of each metal together.

If looked at under a microscope the bond features delicate curlicues in the spots where veins of both materials extend outward and wrap around each other.

In common technique resistance spot welding, manufacturers pass a high electrical current through the pieces of metal, so the metals’ natural electrical resistance generates heat that partially melts them together, forming a weld.

A couple of the drawbacks of the method include consuming high amounts of energy from generating high currents and the melted portions of metal are never as strong afterwards.

The engineers have been able to successfully bond different combinations of copper, aluminum, magnesium, iron, nickel and titanium.

Also bonds, which Daehn states are normally impossible, have been created between commercial steel and aluminum alloys.

Also, high-strength steel and aluminum join together with weld regions that are stronger than base metals.

Manufacturers will also be able to skip a step because the technique is powerful enough to shape metal parts while it welds them together.

Daehn and his team want to continue to develop the technique by collaborating with manufacturers. The new technology will be licensed through Ohio State’s Technology Commercialization Office.

Funded by the Department of Energy and the National Science Foundation, the project was one of the first to participate in I-Corps@Ohio, a new collaboration modeled after and approved by the National Science Foundation’s successful I-Corps commercialization program.

Fully funded by the state, Ohio is the first to have a statewide collaboration based on the National Science Foundation model. The Ohio Department of Higher Education funds and supports the program.

[Back]