Extended DC arc atmospheric pressure plasma source for large scale surface cleaning and functionalization

Plasma technologies at atmospheric pressure (AP) promise efficient integration into industrial manufacturing technology and save considerable investment and maintenance costs. The development of new fields of application of AP techniques increasingly requires the provision of adapted, large‐area plasma sources. The linearly extended direct current (DC) arc plasma source, long arc generator principle (LARGE) for short, with a working width of up to 350 mm was developed at the Fraunhofer IWS for the large area plasma surface treatment. In contrast to other jet‐based AP sources arrays, the LARGE plasma source has a very long afterglow flame length, which makes it possible to efficiently treat surfaces over the range ±40 mm. Especially for large‐area plasma applications, commercial jet nozzle arrays are very complex to control and require more than one power generators which increases the equipment cost. In this paper we discuss selected application fields, namely the rapid (up to 50 m/min) removal of oil films on aluminium sheets, the large‐area functionalization (removal of release agents) of carbon‐fibre reinforced plastic (CFRP) materials, and the deposition of SiO2 adhesive layers on titanium to improve adhesion in the structural bonding of these materials.