"Electromobility has become a sure-fire success"

How electroplating companies should react to the change in mobility. An interview with ESI manager and ZVO automotive expert Rainer Venz.

Tesla's Gigafactory is opening this year, while Volkswagen and other German car manufacturers will only be producing electric vehicles instead of combustion vehicles in the foreseeable future. The age of electromobility seems inevitable. It's like an accelerating train: the transformation of mobility is gathering pace. Instead of 2032, the global break-even point, i.e. the point at which more vehicles with electric than combustion engines are built, is now expected as early as 2029. In Germany, this will already be the case next year. So it's high time to face up to the future reality, because with the change, many coatings will sooner or later be history. Galvanotechnik spoke to Rainer Venz to find out which of them are more and which are less future-proof and how electroplating companies can position themselves in these times. Venz is Global Director Automotive Customer Loyalty, Quality, & Performance Programs at Element Solution Inc (ESI), which now also includes MacDermid Enthone and, since September 1, 2021, Coventya. The new industry giant is now the largest electroplating specialist company in the world. The trained electroplater and current ESI manager Rainer Venz is also Deputy Chairman of the Board of the German Surface Technology Association (ZVO), where he heads the Automotive and Surface Competence Network.

Mr. Venz, with the takeover of your employer Coventya, you are now an employee of ESI. What has changed there from an electroplating perspective?

Rainer VenzVenz: One special feature is that we now combine much more than traditional electroplating technology under one roof. Classic electroplating processes include copper, nickel, chrome and zinc alloys, i.e. everything for corrosion protection, wear protection and decoration. As a result of the new constellation, the Electronics division, which develops, manufactures and sells materials for the production of semiconductors and electronic assemblies, is now also part of the company. The automotive industry is the largest customer across all companies in the Group. And e-mobility is changing the market.

What exactly have you observed here?

I have been tracking production figures for many years, because we only earn money when something is built. According to current forecasts, the global break-even point will come in 2029 and not 2032 as previously predicted. We will then be producing 55 million vehicles with alternative drive systems worldwide. Europe, in particular, will be a positive pioneer because it has_{CO2 fleet targets}. Next year, 18 million vehicles with alternative drive systems are already expected here in Germany. Ultimately, this shows that the focus is on electromobility worldwide and that it is coming to fruition. Regardless of which drive system it is, all alternative drive systems bring us to the point where we have to look at completely new technologies.

You recently published an assessment of the importance of e-mobility for electroplating companies. How can electroplating companies benefit from the trend towards e-mobility in car manufacturing?

Electroplating plants need to be open to change. E-mobility has become a sure-fire success. The question is how electroplating companies can jump on the bandwagon. In my opinion, waiting is the wrong approach; you have to be proactive. Pure combustion engines have many components that are simply no longer used in all-electric vehicles. Exhaust systems, tanks, gearboxes, for example. The list of these components is quite long. Electroplating companies need to ask themselves who they are working for and what they are actually doing. Am I working for a discontinued model or am I already working for other manufacturers who produce components for e-mobility? To this end, electroplating companies should talk to their customers and find out whether they will be manufacturing products for e-mobility in the future and how they can support these manufacturing processes. It is crucial to not only rely on the narrow spectrum of your own portfolio, but also to look beyond it. This may require process changes. For those who do not change anything, things will not turn out so well.

Which processes are more affected, which less?

Electroplating companies that manufacture for the automotive industry should be open to change, e.g. in terms of processes (Photo: Chromorange Budget - stock.adobe.com)If we look at the classic processes, such as nickel-chromium for finishing plastic parts, then they have something to do with vehicle design. This is not initially affected by the trend towards electromobility, although it can be observed that electric vehicles are looking increasingly futuristic and have less and less metal content. There is therefore likely to be a decline in decorative surfaces. However, this is separate from electromobility.

When it comes to corrosion protection, it should be noted that the trend towards alternative drives and e-mobility also includes hybrid drives. With hybrids, there are still certain mechanical components that need to be protected against corrosion. In simple terms, however, it can be said that only half of the components will require corrosion protection in future. The industry will increasingly move towards coating more electrical components.

What is the state of the art in surface technology here?

There are two different areas that are important. One is the classic electroplating of surfaces and the other is the connection and assembly of various components. In the past, this involved screwing, gluing or soldering. Today, for example, electronic components have to be applied directly to heat exchangers. One technique for this is sintering with silver or materials containing silver, which creates a solid connection. This in turn means that far fewer traditional connecting elements such as screw connections are required. At the moment, however, it still appears that electric vehicles contain more connecting elements than conventional combustion engines. However, because more and more gluing, soldering and sintering is being used, we can expect to see an increasing decline in the number of traditional fasteners.

Will sintering find a wide range of applications as a new joining process?

Yes, because it offers many advantages. If you look at a vehicle driving over uneven road surfaces such as cobblestones, there is a lot of torsion at high speeds, as well as bad weather conditions, humidity and possibly also road salt. This can cause classic connections to crack - mechanically through vibration, but also through corrosion or stress corrosion cracking. As a result, components can fail after a relatively low mileage. However, the reliability of components plays a very important role. Surface technology can contribute a great deal here: with sintering systems, but also with other surface technology processes. This applies in particular to future autonomous driving and driver assistance systems.

Lightweight construction remains a trend in e-mobility. What role does electroplating technology play in this?

In future, there will probably be fewer traditional fasteners in vehicles. Instead, there will be more bonding, soldering and sintering. (Photo: Preferi - Fotolia)Lightweight construction is a trend in both e-mobility and classic vehicles. This is why high-strength steels are being used more and more, although they are not permitted for electroplating due to hydrogen embrittlement. However, there are special systems such as zinc-nickel and particularly alkaline zinc-nickel, where the risk of hydrogen embrittlement is significantly lower. This means that classic zinc systems will be less important in terms of corrosion in the future and the use of high-alloy coatings such as zinc-nickel will increase.

What is the situation with aluminum?

Aluminium can be electroplated. However, this is time-consuming and difficult. Today, anodizing is common practice. This creates wear and corrosion-resistant layers that have a good appearance and have been used successfully in window and façade construction for decades.

However, lightweight aluminum construction also involves structural components and brake calipers, for example. For manufacturing reasons, these must be made of higher alloys. However, if you have higher alloyed materials that contain more than 7 percent or more silicon, the classic electroplating processes are actually already over because they can no longer cope with this. However, there are other processes that can be used to anodize components both decoratively and functionally. Painting aluminum is certainly becoming increasingly important, but this also means, for example, that aluminum structural components in vehicles increasingly require coatings for adhesion. These are also required for magnesium materials.

Can coatings be used to improve the material properties of magnesium?

Yes, for me material and surface technology always have a symbiotic relationship. Sometimes you can cut back on the material and maintain the properties via the coating, or you can do without a coating or use a simpler one and use higher quality materials instead. There is no universal recipe. Coatings offer many advantages, such as the prevention of filiform corrosion, i.e. the infiltration of paints; corrosion then stops at the cutting edge. Regardless of the magnesium, 50% of the properties in electroplating come from the electrolytes and 50% from the application technology, according to our observations.

Can you provide figures on the use of materials in automotive engineering with the increasing trend towards e-mobility?

In 2010, around 30% lightweight materials were used - high-strength steels, aluminum, magnesium and plastics. By 2030, this figure is expected to rise to 65%. A lot is changing here. Surface technology must keep pace with this and develop the right processes in collaboration with vehicle manufacturers.

Keyword process engineering. What influence does e-mobility have on electroplating technology?

Everything that goes into the field of electronics will grow. Strip electroplating will continue to be interesting in the field of connectors for electronics. Connectors are finished on the strip, and this can also be done selectively, which saves precious metal. The use of connectors will increase. The topic of PCB technology will also grow. We already have around 15 so-called control boxes with electronic elements in electric cars today. The circuit board has to be coated, but so does the aluminum box with the electronics. It is important that the surface is designed in such a way that no infiltration by corrosion can take place, so that the electronic components are protected from moisture in the long term and a high level of product safety and functionality is guaranteed.

And the use of electrolytes?

In my view, so-called alkaline electrolytes will be more important than acidic ones. For several reasons: With them, the layer distribution is much more even and precise; moreover, sustainability is supported with thin metal-saving layer thicknesses. Alkaline electrolytes also have a positive effect on hydrogen embrittlement - this has already been proven, at least for ZnNi processes.

What opportunities does battery technology offer?

Automotive batteries contain many individual cells that require a certain degree of rigidity to protect them from mechanical damage and prevent fires. They therefore require a very stable housing. Zinc-nickel is often used to protect these steel housings from corrosion. And aluminium is either painted, which means that a conversion coating is needed for the paint to adhere, or anodized to give the component a little more protection against corrosion. Anodizing also offers an insulation advantage, as the process creates an electrically non-conductive surface.

So is targeted conductivity becoming increasingly important?

Yes, because very high voltages are already being used today; in the USA, for example, there is already an electromobility manufacturer that works with 1000 volts in the passenger car sector. The voltage used will increase and the higher the voltages, the more resistant the insulators need to be. To ensure the functionality of these vehicles, leakage and external currents must be avoided. And to achieve this, it is important to direct current in a targeted manner, with targeted conductivity or targeted insulation. The electrical resistances of many surfaces, especially sealants that still set friction values, for example, are often not precisely known. Electroplaters must therefore talk to component manufacturers and use or develop suitable surfaces based on the requirements.

Another aspect of conductivity is thermal conductivity. Thermal management plays a huge role in electric cars in particular, because components are at risk from high temperatures. Thermal insulators must therefore be installed to inhibit or reduce the flow of heat. For other applications, it is important to dissipate heat in a targeted manner.

Conductivity is a major topic in which the industry still has a lot to do. However, the lack of proper testing methods is already a problem. The industry must work together to specify the requirements and test methods and develop uniform standards. In the ZVO Automotive and Surface Competence Network, we are working together with VDA representatives in working groups on the topic of electromobility and electrical properties. We are currently discussing these topics there.