Because conventional coating processes are increasingly coming up against their technological limits and are often too costly, the Fraunhofer Institute for Laser Technology ILT developed a resource-efficient process for laser-based functionalizing of nano- and microparticle materials. As well as being suitable for inline applications, this process is marked by a high degree of flexibility and energy efficiency, while also allowing gentle processing of temperature-sensitive substrates.
Coated bearing and engine components.
Picture source: Fraunhofer ILT. Aachen/Volker Lannert
Conductor paths on glass substrate.
Picture source: Fraunhofer ILT. Aachen
Whether it is transparent conductive layers, conductor paths on semiconductors, anti-reflective surfaces on displays, self-cleaning layers on highly transparent glass, or corrosion, scratch and wear protection layers on components subject to high mechanical stress: in almost every area of industrial manufacturing, there is a great need for functional layers to optimize the surface properties of all sorts of components.
Industrially established processes for the production of high-performance coatings tend to employ vacuum coating processes. But these are costly, as they require elaborate systems technology and due to the required batch processing. More affordable processes, such as electroplating or flame spraying, are either applicable only to certain classes of substrate or else display major drawbacks in terms of the layer characteristics they produce. Coating temperature-sensitive substrates is a particularly thorny challenge in this regard.
Energy-efficient coating of temperature-sensitive substrates
Scientists at Fraunhofer ILT, working with industry partners, have succeeded in developing a resource-efficient laser-based surface functionalization process. This process combines wet-chemical coating processes with a laser process for subsequent functionalizing of the applied material. For example, when coating a glass, plastic or semiconductor substrate, an indium tin oxide (ITO)-nanodispersion is printed onto the component using an inkjet process.
Next, a galvo scanner is used to guide a focused laser beam over the surface to be processed. Laser processing significantly increases the conductivity of the ITO layer, while putting the substrate under far less thermal stress and consuming far less energy than conventional furnace-based coating processes. The new laser-based coating process enables the gentle coating of substrates with a low temperature stability and thereby widens the scope of wet-chemical coating processes significantly.
Locally selective deposition saves on material
Using conventional processes to achieve a locally selective coating of surfaces is not possible or prohibitively expensive in most cases. Functional considerations dictate that any surplus material must be subsequently removed, sometimes using elaborate processes, and this results in an enormous cost disadvantage. In contrast, the fact that laser processes can be controlled with spatial and temporal precision means they are able to functionalize coating materials in exactly the right places on the component and with no wastage.
Suitability for inline applications
A further challenge in functionalizing surfaces is how to integrate the coating process into existing production lines. Conventional processes for a thermal post-treatment (e.g. furnace-based processes) cannot be easily integrated into production lines at low costs. Fraunhofer ILT’s laser coating process poses no such problems, since the printing and laser processes it features are ideal for inline applications. This saves manufacturers a huge amount of time and money.
Fraunhofer ILT’s laser-based coating process can be tailored to meet a wide variety of coating needs. Spatial adaption to the substrate geometry is done by the precise control of the laser intensity distribution. Furthermore the application of pulsed laser beams enables the precise temporal control. Besides creating conductor paths on substrates made of glass, silicon or polymers such as polyethylene terephthalate (PET), it can for instance also be used to apply ceramic corrosion and wear protection layers of zirconium dioxide onto hardened steel. This process is of particular relevance to automotive manufacturing, in which several million components must be coated each year so they can withstand high levels of static and dynamic stress as well as extremes of temperature.
Fraunhofer ILT at Hannover Messe
Our experts will be in Hannover on the joint IVAM booth C50.13 in hall 17 of Hannover Messe from April 8-12, 2013 to present various coated exhibits that highlight the breadth of applications for thin film processing.
Contacts:Dipl.-Phys. Dominik Hawelka
Axel Bauer | Fraunhofer-Institut
No compromises: Combining the benefits of 3D printing and casting
23.03.2018 | Fraunhofer-Institut für Produktionstechnik und Automatisierung IPA
Intelligent wheelchairs, predictive prostheses
20.12.2017 | Fraunhofer-Institut für Produktionstechnik und Automatisierung IPA
Satellites in near-Earth orbit are at risk due to the steady increase in space debris. But their mission in the areas of telecommunications, navigation or weather forecasts is essential for society. Fraunhofer FHR therefore develops radar-based systems which allow the detection, tracking and cataloging of even the smallest particles of debris. Satellite operators who have access to our data are in a better position to plan evasive maneuvers and prevent destructive collisions. From April, 25-29 2018, Fraunhofer FHR and its partners will exhibit the complementary radar systems TIRA and GESTRA as well as the latest radar techniques for space observation across three stands at the ILA Berlin.
The "traffic situation" in space is very tense: the Earth is currently being orbited not only by countless satellites but also by a large volume of space...
An international team of researchers has discovered a new anti-cancer protein. The protein, called LHPP, prevents the uncontrolled proliferation of cancer cells in the liver. The researchers led by Prof. Michael N. Hall from the Biozentrum, University of Basel, report in “Nature” that LHPP can also serve as a biomarker for the diagnosis and prognosis of liver cancer.
The incidence of liver cancer, also known as hepatocellular carcinoma, is steadily increasing. In the last twenty years, the number of cases has almost doubled...
In just a few weeks from now, the Chinese space station Tiangong-1 will re-enter the Earth's atmosphere where it will to a large extent burn up. It is possible that some debris will reach the Earth's surface. Tiangong-1 is orbiting the Earth uncontrolled at a speed of approx. 29,000 km/h.Currently the prognosis relating to the time of impact currently lies within a window of several days. The scientists at Fraunhofer FHR have already been monitoring Tiangong-1 for a number of weeks with their TIRA system, one of the most powerful space observation radars in the world, with a view to supporting the German Space Situational Awareness Center and the ESA with their re-entry forecasts.
Following the loss of radio contact with Tiangong-1 in 2016 and due to the low orbital height, it is now inevitable that the Chinese space station will...
Fraunhofer Institute for Organic Electronics, Electron Beam and Plasma Technology FEP, provider of research and development services for OLED lighting solutions, announces the founding of the “OLED Licht Forum” and presents latest OLED design and lighting solutions during light+building, from March 18th – 23rd, 2018 in Frankfurt a.M./Germany, at booth no. F91 in Hall 4.0.
They are united in their passion for OLED (organic light emitting diodes) lighting with all of its unique facets and application possibilities. Thus experts in...
A new scenario seeking to explain how Mars' putative oceans came and went over the last 4 billion years implies that the oceans formed several hundred million...
23.03.2018 | Event News
19.03.2018 | Event News
16.03.2018 | Event News
23.03.2018 | Materials Sciences
23.03.2018 | Agricultural and Forestry Science
23.03.2018 | Physics and Astronomy