An aluminum alloy developed in the 1940s has long held promise for use in automobile manufacturing, except for one key obstacle.
Although it's nearly as strong as steel and just one-third the weight, it is almost impossible to weld together using the technique commonly used to assemble body panels or engine parts.
That's because when the alloy is heated during welding, its molecular structure creates an uneven flow of its constituent elements -- aluminum, zinc, magnesium and copper -- which results in cracks along the weld.
The solution: infusing titanium carbide nanoparticles -- particles so small that they're measured in units equal to one billionth of a meter -- into AA 7075 welding wires, which are used as the filler material between the pieces being joined.
A paper describing the advance was published in Nature Communications.
Using the new approach, the researchers produced welded joints with a tensile strength up to 392 megapascals.