Etching Instead of Welding New Bonding Technology for Aluminium
Researchers have developed an etching process that allows them to establish a stable bond between aluminium and aluminium alloys as well as between aluminium and plastic. This can be an alternative to any welding and bonding processes.
In order to connect metal components, they are usually welded locally. The high temperatures required for this very laborious process can cause structural distortions or optical changes in the material. A team of the Functional Nanomaterials working group at the Christian-Albrechts-Universität zu Kiel (CAU) and the Kiel-based technology company Phi-Stone have developed a flexible process that could replace the conventional welding or bonding methods: Nanoscale sculpturing is a special etching process used to create a stable and permanent bond between aluminium and aluminium alloys as well as between aluminum and plastic materials.
"Process Works at Room Temperature"
"Our process works at room temperature and without special protection measures. In addition, it can be used flexibly, even in places that are difficult to access, such as corners or upside down on the ceiling," says Prof. Rainer Adelung, who heads the CAU research group.
In order to bond metals, the scientists roughen the surface in an electrochemical etching process that creates a fine, parallelepipedal barbed structure at the micrometer level. When two surfaces treated in this way are glued together, their process creates a connection within minutes that is very difficult to detach. "If something breaks, then it is most likely the adhesive or the materials themselves, but not the connected area,” emphasizes Ingo Paulowicz, Chairman of Phi-Stone.
Subsequent Attachment of Components
Adelung is convinced: "The nanoscale sculpturing process opens up new possibilities in joining technology, but also for new combinations of materials such as of aluminium and copper or silicone.” His team sees possible areas of application in shipbuilding, aircraft and vehicle construction. The process is particularly suitable for retrofitting components in existing constructions.
The researchers developed the mobile and easy-to-use Metalangelo prototype to enable industrial application of their joining process. Etching cells that can be individually produced in a 3D printer, can process metal surfaces accurately at room temperature. Together with first customers, the scientists want to further develop the product to make it market-ready. Two patent applications have already been filed.