Professor Burr, research into innovative surface technology is gaining more and more attention as a means of competitive differentiation and safeguarding industrial locations – not just within companies but also within politics. What do you believe is the reason for this trend?
Surface engineering is a key area of technology. Without resistant surfaces things like mobile aerials wouldn’t survive the weather very long, cellphone screens would fade – without biocompatible surfaces, implants would be rejected immediately. From a societal point of view, we need surface engineering to solve global issues in a variety of areas, such as climate and energy, transportation, food, environmental protection, and health care. These are the markets of the future and surface technology will play a role in opening up these markets. Research into materials and surfaces is a core building block in safeguarding Germany’s role as an industrial nation. The Steinbeis Transfer Center Plastics Center is also making important contributions to surface engineering. Politicians expect the necessary funding for this to be made available by the German Ministry of Research.
The work of your Steinbeis Transfer Center revolves around your interest in plastics. One key area of this is injection molding technology, which is tremendously important when it comes to production in mass markets. What challenges does this technology face at the moment? Is there a trend toward Germany returning to more plastics production in the future?
Injecting molding has been an established part of the profitable production technology used for molded plastic parts for a long time, especially for high-volume parts. Aside from extrusion, it’s the most important processing technique. The biggest challenge lies in the commercial pressure to continually raise automation levels at the maximum possible energy efficiency. In recent years, there’s been a rapid rise in the number of complex applications that require different functions – from the same molded part, in specific combinations – so over the last decade a large number of special injection molding processes have been developed, involving technically intricate machines and tools. These developments serve to strengthen Germany as a producer. But I’ve not observed any significant trends back toward more standard injection molding production in Germany.
There’s a small revolution going on in production technology, with the development of so-called 3D printers – at least there is in the production of prototypes. Will this innovation have a decisive impact on injection molding?
In terms of prototype construction and plastic products in small batches, there are huge expectations in the plastics industry that 3D printing technology or a similar process will provide a commercially viable alternative relatively soon. Breakthroughs already appear to have been made with the quick manufacture of first-stage plastic parts and components, based on initial designs. But whether these parts will ultimately be good enough to fulfill quality expectations can’t yet be answered with a “yes,” and, in the future, this will remain a fascinating area for research and development.
Turning to lightweight construction, which is growing in importance, a key role here is played by glass-fiber and carbon-fiber reinforced plastics (GFRPs and CFRPs). Until now, production has still been a largely manual process. How much potential is there to automate these processes?
As in the past, the trend is still to use fiber-reinforced components even in mass production, especially in the automotive industry (CFRP). This is mainly because, ignoring the argument about the lightweight construction, compared to existing technology, these parts make it possible to integrate a relatively high number of different functions and they leave a lot more leeway for different design options. In terms of recycling, this trend could be viewed more critically, however. But there is still a long way to go in terms of exploiting the full potential to automate processes. We’re currently working on a research project at the University of Heilbronn to halve the curing time of matrix resins used in CFRP car bodywork components by using a special dynamic temperature channeling technique on RTM pressing tools. This should also improve component quality. Downstream processes can also be optimized by using modern laser technology. Also, the level of automation can be raised by using machines like robots to lay sheets into the molds.
The future of surface technology will be strongly dictated by economic and social trends. For example, new processes in this area could enhance energy efficiency or lead to innovative medical equipment or sustainable transportation. What do you believe the future holds for the industry and what topics will shape the next few decades?
In the foreseeable future, markets shaped by the trend toward sustainability will experience significant growth. A number of recent studies underscore this. Technologies named in this context include powerful energy storage solutions, decentralized power generation, the use of renewables, new mobility concepts, personalized health care, and infrastructure matched to the needs of the elderly. Surface technology plays an important role in most of these “sustainable markets of the future.” Depending on the area, certain properties are needed – surfaces that are extremely smooth, or rough, adhesive, hydrophobic, hydrophilic, bactericidal, biocompatible, rigid or flexible.
The following examples highlight the importance of surface technology. Durable, corrosion-, friction-, and UV-resistant surfaces are now indispensible in solar panel equipment and reflectors used in large solar heating systems. Special coatings used in vehicle powertrains significantly reduce energy losses by minimizing friction. Special structures added to the surfaces of rotary blades on wind farm equipment and the outside of aircraft ultimately help reduce aerodynamic losses. By adding minute functional surface structures at the nanometer level to plastic parts, it is possible to make antireflective glass, antireflective layers on solar energy modules and monitors, or hydrophobic and hydrophilic surfaces. Tribological, haptic, and biocompatible properties can be influenced by specifically structuring micro- and nano-engineered surfaces. Recent processing techniques, such as a highly dynamic variotherm injection molding technology developed at our Steinbeis Transfer Center, now make it possible to produce precision parts economically out of thermoplastics and include these kinds of functional surfaces in mass products. This is leading to new products with specific functional properties – of major interest to all sectors of industry!
Professor Dr.-Ing. August Burr
Steinbeis Transfer Center Plastics Center (Bretzfeld)