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Agency: European Commission | Branch: FP7 | Program: CP-FP | Phase: NMP-2007-2.1-2 | Award Amount: 4.74M | Year: 2008

The aim of this project is to develop high density defect-free ultra-thin sealing coatings with excellent barrier properties and improved corrosion resistance. Their successful functioning will be provided by the synergy of the coating perfect morphology and its complex structural design, which can be tailored at the nanoscale. The study will be focused on development of novel nanostructured coating systems, such as nanoscale multilayers, mixed and composite coatings. These impermeable sealing layers must be able to block the ion exchange between the substrate material and an aggressive environment, thus offering an efficient protection against corrosion over a long term. The coatings will be deposited by four alternative vapour deposition techniques, Filtered Cathodic Arc Deposition (FCAD), High Power Impulse Magnetron Sputtering (HIPIMS), Atomic Layer Deposition (ALD) and Plasma Enhanced Atomic layer Deposition (PEALD)). These techniques possess a unique advantage offering the deposition of highly conformal and uniform films of high density, free of defects. The technological objective of the project is to demonstrate the feasibility of corrosion protection by FCAD, HIPIMS and ALD techniques on an industrial scale. To fulfil this objective, a complete industrial process for the multi-stage surface treatment, including cleaning, pre-treatment, coating deposition, must be defined. All techniques will be evaluated in terms of technical effectiveness, production costs, environmental impact and safety, and the most suitable technique(s) will be selected for further development on a large scale for the applications in some targeted industrial sectors. The applications, tested within this project, concern high precision mechanical parts (bearings), aerospace components (break systems) and gas handling components. The coating application in the decorative and biomedical domains will be assessed.

Agency: European Commission | Branch: FP7 | Program: BSG-SME | Phase: SME-1 | Award Amount: 1.47M | Year: 2008

The European jewellery industry is facing a severe competition from Far Eastern countries on both home and export markets. The import of large volumes of low cost jewellery puts the margins under pressure. European companies, often employing less than 10 persons, traditionally show poor attraction for co-operation and research. This attitude hinders changes and innovation, though current production methods have rejection rates up to 20 or even 30% and up to 25% of job places could be lost in the sector over the next five years. Aim of this project is to introduce a new approach into jewellery design and production, through the development of a simulation tool on broad basis, the exploitation of the full potential of existing Rapid-Prototyping Technology and the use of Design of Experiment. Detailed research and analysis will be carried out both on materials properties and on processes, the latter being examined both at a laboratory and industrial scales. The SME proposer group represents the entire chain of suppliers, manufacturers and developers of jewellery materials, equipments and technology. RTD performers consist of complementary research partners with large and worldwide recognised experience. The strength of the consortium is unique, guaranteeing actuality and quality to the work to be performed, resulting in an estimated increased turnover of 20% in the first two years for the SMEs. Research results will be filtered, with the aim of extracting the main outcomes and recommendations of general applicability relevant for process innovation in the gold jewellery casting industry. Training sessions will be held, aiming at focussed transfer of the increased knowledge to the casting technicians, production engineers and product designers. The research and sustainable knowledge transfer will thus enable SMEs to offer new and innovative products to their customers, contributing to the increase of competitiveness of the European jewellery sector.

Beck G.,Research Institute for Precious Metals and Metals Chemistry | Bretzler R.,Research Institute for Precious Metals and Metals Chemistry
Materials Chemistry and Physics | Year: 2011

On aluminium single crystals with (1 1 1), (1 1 0) and (1 0 0) orientation, nanoporous alumina layers were formed in a two-step anodization process within sulphuric acid. The pore ordering within the hexagonal arrangement of the nanopores was documented by scanning electron microscopy (SEM), described on the basis of defect thermology and analyzed quantitatively by image evaluation. The best ordering was obtained in nanoporous alumina on (1 0 0) aluminium. We supposed that this is caused by the interface energy term within the driving force for the formation of the nanoporous alumina, since - in contrast to (1 1 1) and (1 1 0) aluminium as substrate - in the case of (1 0 0) aluminium the interface energy is minimised in the waved interface between aluminium and hexagonally arranged nanoporous alumina. © 2011 Elsevier B.V. All rights reserved.

Balzer M.,Research Institute for Precious Metals and Metals Chemistry | Fenker M.,Research Institute for Precious Metals and Metals Chemistry
Surface and Coatings Technology | Year: 2014

High power impulse magnetron sputtering (HIPIMS) is known for ionising a reasonable amount of the deposition particles emitted from a magnetron sputtering source. Besides improved density and mechanical properties of the deposited films a higher thickness uniformity in three-dimensional structures has also been reported as a benefit of this technology. In this work TiC thin films were deposited from a 50mm diameter TiC-target in Ar atmosphere using direct current magnetron sputtering (dcMS) and HIPIMS with a peak power density of 1kW/cm2. A special three-dimensional structure with three different drilled blind holes (10, 4 and 2mm diameter) was built and used as the substrate. Flat polished high speed steel samples were mounted as parts of the side wall and the bottom of each hole in such a way that the coating thickness and hardness could be detected afterwards at several locations. It turned out that in most cases HIPIMS did not show any improvement in the homogeneity of the film thickness. In fact mostly the dcMS deposited films even exhibited better thickness uniformity. However, the differences between dcMS and HIPIMS remained rather limited at an Ar pressure of 0.4Pa, whereas at 1Pa they have been much more significant. Applying a substrate bias voltage of -50V again nearly did not show any important impact. On the other hand the film properties in part changed distinctly. The hardness of the dcMS deposited TiC-films at the hole walls was up to 4 times lower than that of the HIPIMS deposited ones. Examination of the samples prepared by focused ion beam (FIB) and observed by scanning electron microscopy revealed a far more porous film morphology as an obvious reason for the severe drop of the hardness of the dcMS films at the side walls. The samples facing the magnetron exhibited very high hardness values (>2500HV) which were nearly independent of the deposition method. A detailed overview and discussion of the data will be provided, together with ionisation data obtained by optical emission spectroscopy. © 2014 Elsevier B.V.

Beck G.,Research Institute for Precious Metals and Metals Chemistry | Janek J.,Justus Liebig University
Solid State Ionics | Year: 2012

Platinum and Palladium films were prepared on (111) orientated yttrium-stabilised zirconia (YSZ) by pulsed laser deposition (PLD). Afterwards, the Pt/YSZ and Pd/YSZ systems were annealed and/or electrically polarised. The polarisation was performed in the manner that oxygen was alternatingly built-out and built-in (= cyclovoltammetry experiment) at and within the metal films. The as-deposited, annealed and polarised films, respectively, were characterised by EBSD, SEM, X-ray pattern and pole figure measurements. In addition, the X-ray patterns were measured in situ during annealing and during polarisation. The as-deposited metal films were nearly single crystalline, but with twins of a size between 100 nm and 300 nm as defects. These twins disappear completely during annealing in platinum films on perfect (111) orientated YSZ single crystals and holes are built instead. Whereas-at least a small fraction of-twins remains in films on twin-rich YSZ(111) substrates. Nevertheless, during polarisation these twins also disappear completely, probably due to formation and cracking of oxygen bubbles at twin positions within the metal films. Palladium films behave similarly, but they show stronger de-wetting phenomenon during annealing. They are also oxidised during annealing at an oxygen partial pressure [= p(O 2)] above 1·10 - 3 mbar at temperatures between 500 °C and 700°C or even at this low p(O 2) after some hours at 500°C. During polarisation they are even oxidised at 400°C at p(O 2) > 1·10 - 3 mbar. © 2012 Elsevier B.V. All rights reserved.

Freudenberger R.,Research Institute for Precious Metals and Metals Chemistry
Galvanotechnik | Year: 2012

The significant increase in the price of precious metals in the last two years or so, has increased the pressure on chemical suppliers and electroplaters to achieve savings in their use. Such price increases have, broadly speaking, been seen for all precious metals so that substitution, for example, of palladium for gold brings little benefit. Only increased use of selective coating is an option. A second issue of growing importance is eliminating the use of undesirable materials. Under this heading, now as in the past, is use of cyanide but also additives such as lead or cadmium. There is great interest in the use of nanomaterials in the context of precious metal deposition. Above all, requirements from the fields of electronics and electrical technology both focus on the properties of electrodeposited precious metals and modified forms of these.

Fenker M.,Research Institute for Precious Metals and Metals Chemistry
Galvanotechnik | Year: 2012

Pulsed sputtering processes have long been used for the deposition of insulating layers in vacuum coating systems. HiPIMS is a new generation pulsed sputtering process using extremely heavy duty pulses. This results in a high degree of ionisation of the sputtered particles in the plasma, thereby improving the coating properties. In addition to the many advantages of this process (improved adhesion, higher density of coating, increased wear resistance), it also has certain drawbacks (e.g. lower deposition rate). As well as an introduction to HiPIMS technology, its scope and limitations are also discussed.

Balzer M.,Research Institute for Precious Metals and Metals Chemistry
Thin Solid Films | Year: 2014

Coatings deposited by Physical Vapour Deposition techniques have been characterised for decades for their corrosion protection capabilities. The coating microstructure has often been stated to be the key factor. Improvements, mostly based on electrochemical corrosion measurements, often did not prove true when verified by neutral salt spray test. The pitting corrosion then observed has usually been explained by the presence of growth defects. With the Large Area High Resolution mapping a method has recently been developed which allows localizing and characterising the growth defects responsible for pitting corrosion attacks. It is based on scanning the topography of the entire surface (several cm2) of lab sized coated samples with a lateral resolution in sub-μm range by confocal microscopy. Using this method on the same sample before and after a corrosion test enables to trace back the corrosion pits to their responsible growth defects. Furthermore reliable defect statistics, defect maps and Cartesian coordinates for each individual defect are available. The method is introduced in detail including issues that had to be solved like dust particles being present on the sample surfaces during the scan. Finally results for TiN coatings deposited by dc magnetron sputtering are presented. These results indicate that large as well as very small growth defects are the only reason for pitting corrosion attacks on the investigated samples. A corrosion relevance of different defect sizes is determined and correlations between the defect concentration and the appearance of the samples after the neutral salt spray test are presented. © 2014 Elsevier B.V. All rights reserved.

Klotz U.E.,Research Institute for Precious Metals and Metals Chemistry
Gold Bulletin | Year: 2010

Blue and purple gold alloys form in the alloying systems of gold with gallium/indium and aluminium respectively and are known to be very brittle and to possess low corrosion resistance. Taking into account these drawbacks this paper describes the results of a European funded research project. The properties of the blue and purple gold alloys and coatings such as corrosion resistance, metal release rates, hardness and colour and the influence of alloying additions on these properties are presented and discussed. Surface engineering techniques and investment casting were used for manufacturing of jewellery items with selectively coated coloured surface. Coatings of AuGa 2 and AuIn 2 blue gold alloys were applied on 18kt gold and Sterling silver jewellery by electroplating, laser/torch cladding or dipping into liquid gallium. The suitability of blue gold coatings for jewellery purposes will be discussed in the light of reliability and feasibility. The work consists of two parts. Part I describes properties and surface processing techniques while Part II deals with investment casting and related alloy design of coloured gold alloys.

Freudenberger R.,Research Institute for Precious Metals and Metals Chemistry
Galvanotechnik | Year: 2011

Scanning the literature on precious metals in 2009 reveals that the emphasis is overwhelmingly on the Platinum Group metals, in particular platinum and palladium. The activity in development of palladium-based solutions is presumably due to its cost advantage as compared with gold and has resulted in significant improvements in the industrial uses of palladium alloy electrolytes. Cost pressures are also evident in respect of platinum electrodeposition of catalysts where catalysts based on platinum combined with non-noble metals continue to find new applications.

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