Beschichtungen für Life Science

Coatings for Life Science Thin film technologies being well known from semiconductor industry and corresponding technologies for microstructures are successfully used in Life Science (medical technology, pharmaceutical research or biology). These technologies are the base of the complex and miniaturized life science products. Life Science is a strongly growing part of microsystems technology enabling innovations like the cochlear implant replacing the human ear or new products like the retina implant, the latter being shortly before market entrance. Since 1960 the use of plastic material in this field grew rapidly and still today it is a growing market for plastic material manufacturers. The reasons are cheap production and easy way to sterilize plastic material disposables.Unfortunately in many cases plastic materials do not possess the desired surface properties. But an additional (functional) coating may lead to the necessary properties. Low pressure vacuum technology as a sub group of vacuum coating technology is well suited for this surface modification. Normally process temperatures are only between 20 °C – 60 °C. Ceramic and metal based products in Life Science can be modified, too. There is a wide range of coating applications e.g. diamond like coatings on stents leading to decreased thrombus formation. In this overview basics of vacuum coating technology and plasma technology are described and examplarily some aspects and applications in Life Science are shown.     

PVD‐Beschichtungen für trockenlaufende Hybridwälzlager

PVD coatings for dry running hybrid roller bearings PVD coatings are able to improve the characteristics of dry running hybrid roller bearings. Wear and friction moment can be reduced by coatings. Therefore PVD coatings were adjusted for the appearing loads. Examinations with the help of the standardised FE8 test‐rig were used to verify the potential of PVD coatings in dry running applications. The results of the tests were taken into account for further coating development.     

Anforderungen an Beschichtungen für den optischen Gerätebau

Demands on Coatings for Optical Devices Growth in optical technologies requires reliable optical equipment composed in important parts by high quality optical thin film components. Outstanding performance in coatings is an essential demand for optimum functionality and overall stability of the optical apparatus. Developmen of new / hybrid film deposition techniques for industrial use and search for new materials and improved film system design are strictly required.     

Maßgeschneiderte Beschichtungen für moderne Isolierglasanwendungen

Customized coatings for high performanceglazing The article considers the state of art in Low‐E Glazing Technology. Technological circumstances are discussed as well as the practical use of modern insulating glass products. Some trends in the development of coated products are mentioned in an overview.     

Kohlenstoffbasierte Beschichtungen für automotive‐Komponenten

Carbon‐based coatings for automotive components The outstanding properties of carbon‐based coatings are the low friction against steel and the wear resistance, interconnected with the high hardness. In lubricated systems coatings only work in the mixed and boundary friction regime; this means as long as primary body and counter body are still in contact. The properties of coatings can be adjusted in wide ranges. A purposeful adaptation requires that the tribological system is sufficiently well understood. It has been shown that solutions based on coatings are only sub‐optimal if the coating is only introduced at the end of the designphase. A greater benefit is obtained, when the scope for development as given by a coating is utilized already in the early design phase. The coating is accepted as a design element. To test the suitability of the selected coating quickly and inexpensively in advance, the usual standard laboratory tests are not always appropriate. A test set‐up has to be close enough to the application to generate useful results. These considerations are illustrated using the example of a piston pin coating. The roughness of the primary body and of the counter body is of particular importance for the adjustment of the coating system, when high loads are applied. The example presented here shows that the usual indicators for surface roughness like R_a and R_z are not always sufficient.     

Nitridische und oxinitridische HPPMS‐Beschichtungen für den Einsatz in der Kunststoffverarbeitung (Teil 1)

Nitride and oxy‐nitride HPPMS coatings for the application in the plastics processing (Part 1) In plastics processing adhesive and abrasive wear are some of the main damage mechanisms. For the wear protection and in order to increase the tool life time as well as to improve the quality of the plastic products, binary or ternary chrome‐based coatings like CrN and (Cr,Al)N deposited by physical vapor deposition (PVD) are used. As the chemical composition of the coating has a significant impact on the surface oxide layer formed after deposition and therefore on the wetting behavior of the plastic melt on the tool surface, the aim on this work was to synthesize different coatings from the system Cr‐Al‐O‐N. Therefore, a nitride coating (Cr,Al)N and two quaternary oxy‐nitride coatings (Cr,Al)ON were deposited by using a dcMS/HPPMS (direct current magnetron sputtering/high power pulse magnetron sputtering) hybrid process by varying the oxygen flux. This articles emphasis is on explaining the influence of varying the oxygen flux during the coating process on the coating properties as well as the composite properties towards the plastic mould steel. On this basis a follow up article in the next issue will concentrated on the more application oriented system properties of the three coating systems towards a polycarbonate melt.     

Nitridische und oxinitridische HPPMS‐Beschichtungen für den Einsatz in der Kunststoffverarbeitung (Teil 2)

Nitride and oxy‐nitride HPPMS coatings for the application in the plastics processing (Part 2) In the previous issue three oxy‐nitridic hard coatings on CrAl‐basis were investigated. These coatings were deposited by physical vapour deposition (PVD) as protective coatings against adhesive and abrasive wear in polymer extrusion. The coatings were developed using a variation of the oxygen content to investigate the influence of the chemical composition on the coating properties as well as composite properties between the coating and the coated tool. Following up on these findings this article will focus on the application oriented system properties of the three investigated coating systems towards the polycarbonate melt.     

PVD‐Nanocomposite‐Beschichtungen für die Zerspanungs‐ und Umformtechnik

PVD Nanocomposite coatings for the machine cutting and deformation technique Physically and chemically separated wear‐protection layers exhibit increasingly more complex structures. Similarly to the a coil of compact materials increase also here solutions develop as composite materials, which are offered in the form of Nanocomposites. An industrially available solution represents the system MeN/Si₃N₄. This is to be introduced concerning its characteristics as well as its application type within the range of the machine cutting and deformation technique.     

Beurteilung der Zuverlässigkeit von Schmiermitteln für die Feinwerktechnik

Assessment of the Reliability of Lubricants for Precision Machinery. The critical examination of the reliability of lubricants for instruments and precision machinery needs first the recognition of all the parameters influencing the efficiency of the lubricants. Afterwards these parameters have to be classified according to their significance of the application of the instruments and precision machinery. These numerous influences cause unexpected and very complicated interactions which often can only be recognized, if the instruments and precision machinery are tested under practical conditions. The very small quantities of lubricants used in the instruments and precision machinery require new techniques for examining the lubricated bearings. A well equipped laboratory and a serious planning of the tests as well are therefore indispensable.     

Verschleißreduzierung an Matrizen für das Präzisionsschmieden von Zahnrädern durch Mehrlagenhartstoffbeschichtung (TiN‐TiCN‐TiC)

Wear reduction on dies for precision forging of gear wheels by means of multi‐layer coating (TiN‐TiCN‐TiC) Due to high thermal, mechanical and tribological loads the tool life quantity of hot forging dies compared to other manufacturing processes is relatively low. Depending on the number of forged parts the mentioned loads lead to different failure causes of the dies. In this connection wear is the main failure cause of hot forging dies. Especially in the precision forging process of gear wheels with its exacting tolerances the tool life quantity is low, which leads to often interruptions of the production process. Because wear concentrates on the near‐surface die areas, these problems can be reduced by increasing the wear resistance of these areas by the Duplex PACVD‐Method, which means nitriding and multi‐layer coating (TiN‐TiCN‐TiC).     

Erweiterung der Anwendungsbereiche für Flüssigkeitsringpumpen

New application horizons for liquid ring vacuum pumps – extended capabilities in combinations with side channel blowers After many years of technical evolution and optimisation for specific applications liquid ring technology accepted is now a widely way of generating vacuum. With the launch of closed circuit cooling systems a plug and play solution with integrated water supply is now available. The combination with the highly efficient and compact side channel blower G‐BH8 leads to a considerably extended performance range and remarkable energy savings.     

Entwicklungstrends in der Scheibenbremstechnologie für Schienenfahrzeuge

Developing trends in disc brake technology for rail application The substitution of conventional ferrous materials by light-alloy solutions gives the opportunity for significant reduction of the rotating masses in the bogie and by that a decrease of energy consumption. The potential of conventional Al-cast-alloys is not suitable to solve this. Castable MMC-materials are a high-promising alternative. Under economic pressure MMC-solutions need not to be only superior but also cost effective. And due to the low ductility of those particulate reinforced materials there is a need for new concepts. Locally optimised disks consist of a ductile carrier [body] with wear resistant rubbing surfaces. This led to several prototype disk brakes manufactured by different casting processes. This paper gives an overview about the state-of the-art and newly developed manufacturing routes and materials, metallic and non- metallic, for rail disk brake application.