After a break of one and a half years, the ZVO Surface Days took place again for the first time at the Estrel Congress Center in Berlin. The event was somewhat smaller than usual - but the atmosphere was good and constructive.

After a break of one and a half years, the ZVO Surface Days took place again for the first time since the beginning of the pandemic at the Estrel Congress Center in Berlin from September 22 to 24, 2021. After it had been uncertain for a while during the planning phase of the event whether an evening event would be possible, the invitation to a Meet & Greet on the first evening of September 22 to kick off the event was a nice surprise. Despite the safety regulations that had to be observed, the reunion with industry colleagues after the long Corona break created a cheerful, almost exuberant mood

ZVO Chairman Walter Zeschky opened the first day of lectures punctually at eight o'clock in Hall 1 and welcomed the participants. Since the annual congress was organized as a Hybrid Edition, in addition to the 305 face-to-face participants, 45 online participants were also able to learn about technological developments, trends and innovations in electroplating and surface technology in 48 lectures or at the booths of the 42 exhibitors. Thus, the number of participants at this year's ZVO Surface Days also fell significantly short of expectations - an experience that many other events have already had to make this year. However, this had no negative impact on the atmosphere and the quality of the event.

In his opening speech, Zeschky expressed his confidence that next year's event in Leipzig would again be able to match the usual number of participants. He also addressed the fact that currently the industry is not only burdened by the effects of the pandemic, but is also facing the challenges posed by technological change in energy generation and use. In particular, the disruption of the supply chain is causing problems for companies, as is the paradigm shift in the automotive industry towards electromobility. Despite these daunting market challenges, however, he said the outlook for surface technology is hopeful - even in the future, almost all products will not be without a high-quality surface.

Next, Dr. Martin Kurpjoweit used the example of the WHW company to show how the surface technology industry has changed over the past decades. The company was founded in 1937 still as a small business, which then moved to the current location in 1977 and has since developed into an industrial company with seven locations.

After the introductory block, the three parallel series of lectures started, each with a different focus. On Thursday morning, for example, climate neutrality was on the agenda and the presentations dealt with decarbonization in circularity as a business model and the energy efficiency of electroplating systems. Under the heading of precious metal surfaces for high-tech products, the company Biconnex presented a new process for producing precious metal coatings with minimal losses - for example in disposable ECG electrodes, where silver-plated plastic elements have to be used.

The established process works galvanically in a drum. The challenge here is that chromium(VI) is no longer permitted for this application in the EU. In addition, silver losses can exceed 11 percent, depending on the bath concentration. Here, a process based on inks with precious metal precursors, which are reduced to metals in a low-pressure plasma, offers an interesting alternative. One disadvantage so far, however, is that the adhesion strength is not as high as with electroplating, but this is not a problem in this application.

The topic block on digitalization in electroplating was also well attended. As an introduction, Peter Schwanzer presented the currently running joint project SmARtPlaS for the Fraunhofer IPA, in the course of which, among other things, a learning and research facility is being set up for development work and pilot applications related to Industry 4.0. Results on the use of new sensors for preventive maintenance were also presented. The approach to further developing material balancing beyond the pure carryover consideration by also including metal deposition, metal dissolution as well as degradation and consumption of substances was interesting.

Also interesting was a contribution by Michael Hellmuth of Softec, who, in addition to the numerous aspects of Industry 4.0 relating to production planning, also made it clear that the competitive advantages resulting from the use of Industry 4.0 and artificial intelligence will decline rapidly from 2024 onwards, because more and more companies will naturally jump on the bandwagon. Christine Maier from Schlötter used practical examples to present new digital applications from their own company specifically for electroplating and illustrated the possible links between the analog and digital worlds as well as the resulting benefits for plant management.

Under the topic From process monitoring to product quality, one of the topics was the faster and more accurate XRF layer thickness measurement. Dr. Cay-Uwe Pinnow presented an important innovation for Helmut Fischer: the use of polycapillary optics in X-ray fluorescence (XRF) layer thickness measurement, which allows the measurement of thin layers down to the nanometer range while maintaining a lateral resolution of less than 20 μm. Due to the high excitation intensity, excellent repeatability should be achieved even at short measurement times compared to devices with collimator optics. In combination with (partial) automation, a highly productive and cost-saving application is also possible in series production.

Approaches to solving problems caused by biofilms and algae in water circulation systems were also discussed. Alois Kinateder from GusChem used practical examples to explain how problems can sometimes be solved by simple measures such as emptying tanks before breaks in operation or air injection to prevent anaerobic areas, or regular removal of lime deposits. In stubborn cases, a change in process chemicals or the use of biocides should be considered.

The young colleagues reported from current research projects and here in detail on the diagnostics of plasma electrolytic oxidation processes as well as of long-term stable, pre-formulated alloy catalysts for high-performance PEN fuel cells. The influence of carboxylic acids on the electrodeposition of chromium from trivalent chromium electrolytes was also addressed. Application-related future technologies, such as the third generation of decorative plating from trivalent chrome electrolytes, for example, for sanitary applications made of brass and zinc die casting, were also discussed. Here, among others, Diego Dal Zilio of Coventya presented the properties of the sulfate-based process Tristar, which is characterized by a high throwing power and, especially in combination with Tristar Shield, by high resistance to chemical influences.

Björn Stroh from Atotech dealt with the topic of pickling inhibitors, why their use makes sense and why, contrary to popular belief, they do not get in the way of the actual pickling process. In this regard, he presented some illustrative and detailed studies. It was shown that modern pickling inhibitors, due to their selectivity, prevent material removal from the substrate as well as hydrogen diffusion into the crystal lattice. At the same time, however, acid attack on inorganic contaminants such as oxides and scale is not mitigated. As a result, the pickling process remains as efficient as without inhibitors, but still achieves a more uniform surface. Since the metal input of the substrate into the pickling solution is reduced, the service life of the baths is improved at the same time. Novel inhibitors achieve efficiencies of over 98 percent and can thus enable hydrogen embrittlement-free pretreatment.

Standardization thrives on participation

A very comprehensive and well-founded look at the subject of standardization was provided by two experts from the DIN Institute, Rainer Paulsen and Janine Winkler. The presentation made it clear that standardization is a very complex subject and that it is worthwhile for companies to participate in the standardization process. After all, standards do not simply fall from the sky, but are defined in cooperation with many experts. In this respect, every company is free to participate itself and thus influence the development and further development of standards. A field report on water-based zinc flake technology in series production on passenger car chassis components of a major OEM was provided by Andreas Tolz of NOF. This involved a corrosion coating for double-shell, welded control arms. In the actual application, zinc flake coating was ultimately approved as the only process for the control arm, as it was the only one that met or exceeded all of the OEM's quality requirements.

Dr. Anika Basuer and David Zapf presented an interesting concept for palladium recovery in plastic electroplating for Hansgrohe. As a result, an efficiency of 60 percent was achieved in the depletion of palladium. When treating all palladium-containing material streams, the plant generated 23,000 euros per month, or nine percent of total palladium consumption. Electroless nickel coatings as a hard chrome alternative were the topic of Jürgen Mayer from De Martin. Standard electroless nickel diamond coatings are produced with particles about 2 µm in size and can cause extreme wear on the friction partner. In this context, Mayer spoke about the advantages of submicron particles and showed, based on test results, that diamond particle sizes of 0.5 µm provide a high level of wear protection under abrasive stress and at the same time have a low abrasive effect on the mating body. This sounds very good, however, it is a challenge to produce the diamond particles in the appropriate size spectrum.

Dr. Sabrina Vogt of Trumpf spoke about the prospects for high-speed laser buildup welding. The advantage with the process, in which the powdered filler material already meets the laser light above the molten bath so that it is heated to close to the molten bath while still on its way to the component, reduces the heat influence zone on the substrate by a factor of 20 to 100. At the same time, the possible feed rate increases by a factor of 50. The surface roughnesses drop considerably by a factor of ten. A considerable increase in productivity can be achieved in this way, particularly in the coating of rotationally symmetrical parts. As possible applications, she addressed hard chrome replacement and the coating of hydraulic components as well as shafts or shanks.

The topic of chromium(III) was also addressed from a wide variety of angles, for example in connection with chromium(VI) substitution. For example, Peter Bötcher from Surtec dealt with the current requirements and further developments of chromium(III) coating systems and showed that a direct substitution of hexavalent chromium processes in decorative electroplating is possible. He also addressed a novel Cr(VI)-free pretreatment for plastic components without permanganates that is currently under development.

48 presentations and a wide range of topics

In addition, there were numerous presentations on sustainability, resource conservation and process optimization - from innovative rack coatings for plastic electroplating and high-quality surfaces for the automotive industry to boric acid-free bright nickel deposition and electroless chromium deposition. In this respect, this year's ZVO Surface Days once again offered a very wide range of information and topics with a total of 48 presentations. Thus, despite the still difficult circumstances for face-to-face events, the Surface Days were an important milestone towards more normality and a better perspective for the future. In 2022, the ZVO Surface Days will take place in Leipzig from September 14 to 16. CB