Fronius uses hot active plasma for surface cleaning

Hot active plasma allows for environmentally friendly, affordable, and reliable cleaning of surfaces to prepare them for coating and joining processes.

The Acerios system developed by Fronius allows for particularly environmentally friendly and cost-effective surface cleaning using hot active plasma. The technology removes organic residues from metal surfaces with pinpoint precision, meaning that in industrial production, components are optimally prepared for processes such as adhesion, painting, or welding.

For example, to be able to join individual aluminum parts to a side wall using spot welding when constructing an automotive body, the surface of the sheets must be freed from foreign particles or film impurities, otherwise a serious lack of fusion would be a possible consequence.

Up until now, the automotive industry has relied on chemical cleaning processes. However, the use, storage, and disposal of the required chemicals is not only expensive, but also problematic in terms of their impact on the environment. Such cleaning processes are also subject to strict safety requirements.

Moreover, nearly the entire component must be immersed in the chemicals, meaning that ultra-precise cleaning is not possible. Overall, this is a laborious and very expensive process.

A technology developed by Fronius can help: hot active plasma removes residues quickly and effectively with pinpoint precision. The application areas range from aluminum and steel through to plastic, glass, and ceramic. The Acerios system generates a plasma flame with a temperature of up to 1,000 degrees Celsius, while a robot guides the welding torch over the surface at speeds of roughly 6 meters per minute.

Depending on requirements, entire surfaces or specific areas can be treated. This significantly increases efficiency, as instead of cleaning as much of the surface as possible, Acerios cleans only those areas that actually need cleaning. This immediately conserves resources, again emphasizing the environmentally friendly aspect of this technology due to the absence of harmful cleaning additives.

By using plasma in its welding technology, Fronius has extensive expertise in this area. The company has also been researching possible applications for plasma in surface treatment for almost ten years, the key to this eventually being found in the generation of atmospheric pressure plasma. This is a hot, gaseous, and energy-intensive mixture of atoms, molecules, ions, and free electrons.

When the hot active plasma comes into contact with a surface, the gas flow mechanically cleans while the plasma and resulting heat trigger a chemical process. This combination of a chemical and mechanical process reliably removes organic residues and film impurities.