Electroplating and surface technology experts meet regularly in March for the Leipzig specialist seminar. This year was no exception, as the event organized by the DGO Saxony and Thuringia district groups was just as successful as last year with 220 participants and 44 exhibitors. However, the participants were once again able to look forward to receiving an electroplating prize in 2024, which was awarded for an innovation in the field of hydrogen production.
Prof. Thomas Lampke introduced the event and moderated the first halfProf.Dr. Thomas Lampke, Head of the Chair of Materials and Surface Technology at Chemnitz University of Technology, opened the specialist seminar with a few words on the general situation in business, research and industry. He described the changing markets and demographic change as a challenge and pleaded for openness to technology and research transfer in order to maintain or rebuild technological sovereignty in Germany and Europe. He affirmed that the industry could make a good contribution here. He called on companies to take these steps boldly. Many complained about the loading, but this was not easy either.
Rich history, investment hotspot and venue for the European Football Championships
From the holistic view of the situation, the moderator then turned to the location of the industry meeting: Leipzig, the largest city in the Free State of Saxony. The city's over 1000-year-old history provided him with plenty of material for a look back. The opera house was built 325 years ago, and the famous St. John Passion by Johann Sebastian Bach, who worked in Leipzig for a long time, has been shaping music history for 300 years now.
Today, there are also positive economic signals for Leipzig
If we look to the near future, a landmark 35 years ago stands out, when the peaceful revolution, the beginning of the end of the GDR, started in Leipzig and then took hold of the entire workers' and farmers' state. Today, there are also positive economic signals for Leipzig: the manufacturer Dräxlmaier is building a new battery plant, the cosmetics manufacturer Beiersdorf a new production center. Several hundred million euros are being invested. Dr. Dörfler from the City of Leipzig mentioned these investments in his welcoming address and at the same time emphasized the importance of the city as the cradle of electroplating, where Georg Langbein laid the foundations for the technology in 1886 with his handbook on metallic precipitation. The city is also eagerly anticipating being the venue for this year's European Football Championships. Four matches will take place here between June 18 and July 2, including the top clash between the Netherlands and France.
Finally, Dr. Daniel Meyer, Managing Director and full-time representative of the DGO, addressed the participants at the Congress Center Leipzig in order to promote commitment in the regional groups. "Approach us with solutions or participation in the regional events," he appealed. The regional DGO representatives Mathias Fritz (Thuringia) and Marion Regal (Saxony), who were sitting in the front row, must have thanked him.
AI in electroplating technology
Dr. Franziska Bocklisch spoke about AI in electroplatingThelecture event of the 29th LFS began with a topic that raises expectations and hopes as well as scepticism: the use of AI. Dr. Franziska Bocklisch, TU Chemnitz, Chair of Materials and Surface Technology, focused her research on the use of AI in relation to electroplating technology. In the first section of her presentation, Bocklisch addressed the questions of how the multi-layered human knowledge of technical processes can be profitably taken into account in the development of AI in addition to the use of measurement data. And how the AI introduction process can be designed to be human-centered in practice in order to achieve positive effects and avoid overburdening employees. It is important to establish a common thread between the conceptual model (expert knowledge), the computer-based model and the user. Bocklisch also reported on an ongoing project. This involves a feasibility study (zinc-nickel electrolyte) at Chemnitz University of Technology on the use of AI in electroplating technology. The investigations were carried out at the robot-supported electroplating plant. The input variables are three electrolyte concentrations and two current densities. The AI modeling was carried out with this data. The process variable is the coating thickness at three defined times. The output variables are roughness and corrosion protection. The initial results of the study are promising. The AI model identified multi-criteria-optimal settings that can be transparently reflected back to the human decision-maker. The results do not yet mean that the process can be optimized, so that further development is necessary.
Reproducible Cr(III) coating thickness measurement
In the second presentation, Dr. Daniel Meyer, DGO e. V., and Dr. Lisa Büker, Kiesow Oberflächenchemie GmbH & Co. KG, presented the results of the round robin test of the DGO working group "Decorative Cr(III) coatings" on the reproducibility of coating thickness measurement for trivalent deposited bright chrome coatings. The aim of the round robin test was to record and neutrally assess various inaccuracies in coating thickness measurement using established methods (coulometry, X-ray fluorescence analysis -XRF) across the industry. Six companies that produced chrome-plated brass substrates and seven companies that produced chrome-plated plastic substrates took part in this first round robin test. The coating thickness measurements were carried out by 14 laboratories using Couloscope and XRF without any special specifications, i.e. as usual in the company. The evaluation of the measurement results was carried out anonymously by the working group leader Büker. Measured values were determined using calotte grinding and FIB as a reference.
The coating thicknesses for decorative Cr(III) coatings have become established in the range of 0.1 to 0.3 µm. The tests showed that the repeatability with XRF is, as expected, good and slightly better than with Couloscope. For samples with very thin layers (< 0.1 µm), the comparability was considerably worse, especially with XRF. This is due to individual and device-specific factors. Therefore, a uniform definition of the measurement task is required for the next round robin test to ensure comparable results. The reference values of spherical section and focussed ion beam (FIB) were often inconsistent. The FIB values give a more harmonious correlation to the couloscope and XRF values. The dome cut is not considered further as a reference value. A second improved round robin test will be carried out, in which the measurement methods will be standardized and the measurement procedure described in detail. Registrations for the second round robin test are still possible.
Optimization of electroless nickel plating
Hans-Joachim Kraft, MacDermid Enthone Industrial Solutions, gave a good overview presentation on innovations to increase productivity, corrosion resistance and sustainability in electroless nickel plating. There are alternatives to the use of PFAS-based wetting agents in electroless nickel dispersion plating. The installation rate, stability and service life of the process as well as the corrosion resistance of the coating with NiKlad ICE Ultra RC correspond to processes based on PFAS wetting agents. Improving occupational safety was the motivation for developing an ammonium and lead-free electroless nickel strike. The NiKlad ELV AF Strike process enables many users to operate their systems completely ammonium-free and significantly simplifies wastewater pre-treatment. With regard to low-concentration electroless nickel, Kraft referred to a US study that demonstrates the reduction of exposure, emissions and metal losses due to carryover with this technology. And a new process with an average deposition rate of 15µm/h is emerging for the deposition of high P.
Energy savings with zinc-nickel coatings
In his presentation, Uwe Knebel, mks Atotech Deutschland GmbH, demonstrated significant energy savings in zinc-nickel coatings through equipment optimization in connection with the mode of action of the electrolyte. The future of economically sustainable alkaline zinc-nickel processes stands and falls with the use of membrane technology. In the process presented, energy savings of up to 32% were achieved by using the membrane system. The disposal of wastewater and sludge containing cyanide and complex substances was reduced by 95% in the closed system. Knebel emphasized that the four components presented for sustainable Zn-Ni plating in the closed circuit: Membrane system, freeze-out unit, vacuum evaporator and the special additives from Atotech (very essential) must interlock. This enables the savings mentioned to be realized. Using application examples (rack and barrel system), Knebel stated that high-quality coatings are achieved by optimizing the system and electrolyte. This turns one of the most raw material and wastewater-intensive processes into an environmentally friendly corrosion protection system. This can also facilitate the approval process for new plants due to the enormous reduction in water and energy consumption and the savings in disposal.
Cyanide-free silver separation
Duringthe coffee and lunch breaks, participants bustled around the 44 stands at the accompanying trade exhibitionInindustrial silver plating, deposition from cyanide electrolytes is still predominant. However, there has been an increase in cyanide-free silver deposition over the last five years. A key aspect in the development of new, environmentally friendly silver electrolytes is the search for new complexing agents for the silver ions.
Silver ions must be sufficiently complexed to enable uniform deposition on less noble substrates
Dr.-Ing. Christoph Baumer, TU Ilmenau, Department of Electrochemistry and Electroplating, provided an approach to the solution with his presentation "Stable, non-toxic complexing agents for silver electrolytes". Silver ions must be sufficiently complexed to enable uniform deposition on base substrates. For the investigations, complexing agents were selected on the basis of the literature, but also in other ways, so that a total of approx. 50 substances were investigated. The electrolytes produced in this way were characterized with regard to the process parameters (pH value: starting at 6-7, as no complexation takes place in the acidic range) and the properties of the deposited layers (e.g. gloss). Based on the investigations, amines and imides crystallized with advantages. However, the low deposition rate, a possible incorporation of the organics and the occupancy of the cathode/anode are currently open points.
Leipzig Electroplating Prize: Efficient and economical bipolar plate coating
After the generous lunch break, technical expert Dr. Olaf Boehnke took over the moderation from Prof. Lampke. The first item on the program for the second half of the event was the Leipzig Electroplating Award, which this year went to a team from Schaeffler Technologies AG & Co. Dr. Mehmet Öte, Head of Surface Technologies, and developer Dr. Sebastian Etschel came to Leipzig to represent the team. With Enertect CT+, the Schaeffler team has developed a coating for bipolar plates of electrolyzers that does not require precious metals, protects against corrosion and is conductive. It is also easily scalable and very economical (more on this in the interview with Dr. Mehmet Öte and Dr. Sebastian Etschel (issue 4/2024)). In his speech, Dr. Öte mentioned that Schaeffler generates a third of its turnover with coatings. That is 5 billion euros. He described electrolysers as an important technology and emphasized their prospects for the industry. The coating was presented by Dr. Etschel, who also thanked Schlötter alongside the other team members. The company had helped drive the project forward.
Leipzig Electroplating Award 2024: Stefan Kaßner, Nehlsen-BWB Flugzeug-Galvanik Dresden, the award winners Dr. Öte and Dr. Etschel, Schaeffler, and Dr. Daniel Meyer, DGO (from left to right)
This year's Leipzig Electroplating Award goes to a team from Schaeffler Technologies AG & Co KG
Schaeffler's new Enertect CT+ coating is part of a product family with different properties, such as Corrotect, Durotect and Tribotect. Etschel made it clear that PEM electrolysers place very high demands on corrosion protection. Enertect CT+ is deposited on the bipolar plate with a layer thickness of 5-20 µm. More details will be discussed in a technical article that will appear in an upcoming issue of Galvanotechnik.
Skills shortage in training
Shortageof skilled workers: These two speakers from the vocational school center for construction and surface technology in Zwickau gave tips on how to recruit trainees, among other thingsTheshortage of skilled workers is omnipresent in the industry. The presentation "Ros(t)ige Zukunft - Anspruch und Herausforderung in der Berufsausbildung" (Rosy future - demands and challenges in vocational training) by Benjamin Trinks, vocational school center for construction and surface technology in Zwickau, gave an overview of the current situation in training, the situation in companies and vocational schools and showed possible approaches and potentials to combat the shortage of skilled workers in the field of electroplating technology. The downward trend in the number of trainees must be stopped. Since 2010, the number of trainees has fallen by around 50%. The main reason for this is that the profession of surface coater is not well known. Trinks blamed this on the renaming of the training occupation. Similar comments can also be heard from the vocational school in Schwäbisch Gmünd. He recommended that the companies go to the schools, present the profession there and thus attract trainees. There is a school database in every federal state where the schools can be viewed.
The number of trainees has fallen by around 50% since 2010
The profession of surface coater must be made more attractive. Companies must work with vocational schools to find ways to respond to the change in learning. Good and experienced trainers and vocational school teachers are also needed. Oliver Schürer, Metallveredlung Kotsch GmbH, acted as co-speaker. Schürer was an apprentice in Zwickau until July 2023. He contributed thoughts on training from his perspective and addressed in particular the fact that trainers often have too little time for trainees due to staff shortages in companies. And it is not uncommon for trainees to be used as unskilled workers, which reduces their motivation for training. Sometimes a lack of mutual respect also leads to a drop in motivation. Schürer emphasized that financial incentives are also very welcome as an incentive for additional tasks. This presentation was a real enrichment of the lecture program.
Value creation trends
"Because there is no planet B", companies have to face the challenges of our time with innovative solutions. Challenges for the electroplating industry include the scarcity of resources, environmental regulations, cost pressure and technological progress.
In water management, processes to reduce the need for fresh water are in demand
In her presentation "Value creation trends - rethinking proven technologies", Daniela Albert, MacDermid Envio Solutions, focused on the recovery of metals, water cycles and reuse as well as process conditioning systems. As examples of resource conservation, she named and explained the freezing out of excess carbonate (and sulphate) from alkaline zinc and zinc-nickel electrolytes, for example, the removal of tramp metals from trivalent chromium baths, the processing of thin and thick film passivation and nickel recovery using ion exchangers. In water management, processes to reduce the amount of fresh water required are in demand. The focus is on the efficiency of recycling, i.e. separate treatment (separation of wastewater streams according to characteristics) and the reuse of recycled water in different rinsing positions depending on quality requirements.
Inline bath analysis
Compared to other methods, the X-ray fluorescence measurement method is ideal for automating the determination of zinc and nickel concentrations in zinc-nickel electrolytes, as no further sample preparation is required. Dr. Marcus Glaum, Helmut Fischer GmbH, presented the in-line bath analysis with X-ray fluorescence (Fischer-scope Xan Liquid Analyzer). The proven Fischer solution measuring cell has been further developed into a flow measuring cell and integrated into a fully automatic measuring system. The device can be used to monitor up to four baths/channels. The channels are separated from each other by separate measuring cells. This prevents contamination between the baths/channels. An automatic rinsing cycle is integrated. With a typical bath composition of 5 - 15 g/L zinc and 0.5 - 2 g/L nickel, the typical reproducibility at 30 s measuring time is 0.3 % for zinc (8 g/L) and 0.7 % for nickel (1.5 g/L). You can read more about this topic in our technical report below.
Photos: Robert Piterek
