WP1 Plasma chemical etching for c-Si photovoltaics
    WP3 Structuring of TCO layers for TF-Photovoltaics
    WP5 Infection control: Process and Materials studies
    WP7 Energy storage – Process and materials R&D
    WP9 Interface technologies for durable adhesion
    WP11 Cross-cutting equipment development

Aim is the development of interface technologies to improve bond strength of adhesively bonded or painted components in the aerospace and automotive industry.

Main aspect of the aeronautic industry is the increase of bond strength on titanium and carbon fibre reinforced plastic substrates of adhesively bonded parts especially with respect to long term stability of adhesion.

Focus of automotive industry is the reduction of failure rate of painted thermoplastic surfaces (polypropylene PP) compared to state-of-the-art processes.

Adapted lab scale equipment will be used for process development of interfaces by surface modification or surface coatings to improve bond strength on flat substrates. In parallel a technology head (demonstrator) will be developed for robot based use on 3-D components within WP 10.  Results in work period M1-18 are:

Equipment: Lab equipment is developed/adapted and used for process development. The coater head design and fabrication is in progress. Improvements to reduce weight of the coater head are under experimental examination.

Process:  The beneficial effect of SiOx-based coatings as adhesion promoting interface has been demonstrated for titanium. Long term stability of bonds has been improved compared to industrially available wet chemical treatment. To match the baseline of NaTESi treatment (EADS proprietary process, to be replaced due to environmental constraints) further optimisation is necessary.

For PP it was demonstrated, that atmospheric plasma treatment results in nano-structured, chemically modified surfaces. The adhesion of paints on those surfaces is substantially increased compared to non-treated samples, but does not yet reach the values of conventionally treated reference samples. This is especially noticeable with a newly developed peel test, which generates quantitative results of adhesion. Variation of plasma parameters is by far not exhausted and will be used to optimise the surface modification process towards industrial requirements.