Entwicklung der Prozesstechnologie für massive metallische Gläser auf Platinbasis mit dem Ziel einer Industrialisierung am Beispiel des Uhren- und Schmucksektors

Platinbasierte massive metallische Gläser (Pt-MMG) sind revolutionäre Schmucklegierungen mit besonderen Eigenschaften. Ihre hervorragende Oberflächengüte und hohe Gusshärte (400–500 HV1) begünstigt die präzise, formgetreue Abbildung und macht die Nachbearbeitung überflüssig. Pt-MMG sind hart wie Stähle, besitzen aber eine kunststoffähnliche Elastizität und Flexibilität. In einem Forschungsprojekt konnten diese Platingläser erstmals mit dem in der Schmucktechnologie etablierten Feingießverfahren verarbeitet werden. Dank ihrer einzigartigen Qualitäten eröffnen sich der Luxusgüterindustrie damit völlig neue Designmöglichkeiten.

Dem fem und seinem Forschungspartner LMW ist es gelungen, gemeinsam mit Partnern aus der Industrie das industrielle Potenzial von Pt-MMG am Beispiel von Uhren- und Schmuckanwendungen zu demonstrieren und den Technologiereifegrad anzuheben. Mit den amorphen Platinlegierungen konnten feine Geometrien mit komplexen Füllwegen realisiert werden. Die Schmuckobjekte sind trotz ihrer filigranen Struktur mechanisch stabil und weisen eine außerordentlich hohe elastische Verformbarkeit auf. Im Druckgusserfahren konnten zudem auch massivere Bauteile wie Uhrenlünetten hergestellt werden. KMU bietet diese neue Technologie die Chance, in den Platinschmuckmarkt einzusteigen und ihre Wettbewerbsfähigkeit zu erhöhen.

Haben wir Ihr Interesse geweckt? Unsere Expertin Lisa-Yvonn Schmitt freut sich auf Ihre Kontaktaufnahme!

Danksagung: Das IGF-Vorhaben 21469 N der Forschungsvereinigung Verein für das Forschungsinstitut für Edelmetalle und Metallchemie (fem) wurde über die AIF im Rahmen des Programms zur Förderung der Industriellen Gemeinschaftsforschung (IGF) vom Bundesministerium für Wirtschaft und Klimaschutz aufgrund eines Beschlusses des Deutschen Bundestages gefördert.

Qualification of Standardised Long-Term Tests on Copper Materials for the Economic Determination of Material Parameters for CAE Applications

Long-term tests practically used to characterize the material behavior of copper materials are only limitedly suitable for identifying reliable input data for CAE applications such as the Finite Element Method (FEM). However, due to increasing demands on copper components, such as used in electrical connectors, more precise knowledge about this input data is essential for a safe and resource-efficient component design. Therefore, it was the aim of this project to develop a method for determining material parameters for copper materials from long-term tests based on the ASTM standard [AST13] in an economic way. The determined parameters are supposed to describe the analyzed copper materials more precisely and are usable directly as input for simulation-based component design.

Within the project, it was assumed that a unique relationship between the measured parameters of the ASTM tests (e.g. cantilever tests) and the time- and temperature-dependent properties of copper materials is existing. This relationship, however, cannot be directly determined from these tests. Instead, it was the aim to determine this relationship based on numerical methods and machine learning techniques. To obtain the necessary experimental data, a suitable test setup was developed. This enabled inferring the time- and temperature-dependent material behavior or model parameters for a selected material model directly and cost-efficiently from the measured quantities of an ASTM test.

The benefit of the project is that significantly more precise information about the long-term behavior of copper materials can be obtained from already established standard tests without increasing the experimental effort. SMEs can use the results as direct input for CAE applications. In addition, SMEs can design components more cost and resource-efficient using a description of the material behavior, which is more accurate as it was before. The results of this project can be transferred to other materials, for which the long-term behavior is also relevant.

Haben wir Ihr Interesse geweckt? Unsere Expertin Karin Pfeffer freut sich auf Ihre Kontaktaufnahme!

Innovative Composite Material for Investment Casting of Titanium Alloys

The production of complex technical components from titanium alloys using the investment casting process is of great interest for aeronautical engineering, space technology, medical technology and the luxury goods industry. The ceramic material calcium zirconate (CaZrO₃) enables the extremely demanding investment casting of titanium, but exhibits weaknesses in thermal cycling. Crucibles made of CaZrO₃ show cracks after only one casting due to thermal shock and can only be reused to a limited extent afterwards.

The fem has succeeded in creating an innovative composite material that solves this problem by adding electrospun CaZrO₃ nanofibres. In the research project, it was demonstrated that thanks to the modified microstructure, the material has a significantly higher stability against thermal loads and consequently a high residual strength after casting. As a result, CaZrO₃-based composite crucibles are finally suitable for repeated use in investment casting. This development enables investment foundries to process highly reactive alloys in high quality significantly more efficiently and economically.

Have we aroused your interest? Our expert Florian Bulling is looking forward to hearing from you!

Acknowledgements: The IGF project 21706 BG of the Research Association for the Research Institute for Precious Metals and Metal Chemistry (fem) was funded by the Federal Ministry of Economic Affairs and Climate Action through the AIF within the framework of the Programme for the Promotion of Industrial Cooperative Research (IGF) based on a resolution of the German Bundestag.

Development of new active solder alloys by ultrasonic plasma atomisation for the joining of ceramic-ceramic and metal-ceramic composites

Available active solder pastes are almost exclusively based on silver and silver-copper alloys, which limits the temperature stability of the composites. Higher temperature stabilities can be achieved with active solders based on precious metals (Pd, Pt), but these are significantly more expensive. There is therefore a need for new types of active solder alloys that enable stable composites for application temperatures of 1000 °C to approx. 1200 °C. In addition to the main interest in the feasibility of corresponding composites, the pure metallisation of functional ceramic surfaces for electrical contacting is also of interest. 

Active solder pastes are usually required in small quantities, but in a large variety, specialised and optimised for defined applications. With ultrasonic plasma atomisation, it is possible to realise small batch sizes and alloy systems that are difficult or impossible to mix using melting metallurgy. To this end, new active soldering systems, the fundamentals of which are already known, are to be evaluated, optimised and adapted. In addition to powder production, matching the pastes to the active solder application is a very important aspect. Rheological properties and solids content must be adapted for industrial, automated application of the solder pastes using screen printing and dispensing technology. In addition, reliable debinding in a vacuum must be possible. The investigations are supported by statistical design of experiments (DOE) and multivariate data analysis (MVDA) in order to ensure a high level of efficiency with regard to the variety to be analysed and a higher significance of the results.

The aim of the research project is to develop temperature-stable active solder alloys that are not based on precious metals, to produce powder using ultrasonic plasma atomisation and to optimise active solder pastes. Active brazing technology enables the realisation of metal-ceramic composites in just a few process steps, as direct wetting of ceramic surfaces is possible. The application of these solders as powders or pastes has advantages over moulded parts (wire, foil) in terms of automated applicability (screen printing, dispensing) and minimises material losses. 

The IGF project 22117 BG of the research association Verein für das Forschungsinstitut für Edelmetalle und Metallchemie (fem) is funded via the AIF as part of the programme for the promotion of joint industrial research (IGF) by the Federal Ministry of Economics and Climate Action on the basis of a resolution of the German Bundestag.

Material Digital

As part of the MaterialDigital project, it was demonstrated for the first time that materials can be integrated into digital value chains in the sense of Industry 4.0. For this purpose, digital representations of the processed materials (so-called material twins) were generated from a material data space for the two use cases of metals and polymers during the manufacturing process, thereby achieving consistency of the material status information along the process chains under consideration. This has the advantage that the processes can subsequently be optimised with regard to the desired local, physical or mechanical properties of the materials. 

The integration of materials in value chains in the sense of Industry 4.0 was demonstrated using two use cases. The aim here was to use digital twins to ensure the consistency of material properties that vary in terms of location and time along the value chain or product life cycle.  

In the metals application (in which the fem was involved), the aluminium gravity die casting process with subsequent two-stage heat treatment (solution annealing and artificial ageing) was considered. The casting alloy AlSi10Mg served as an example alloy. In two casting campaigns, test bars were initially cast on the fem in order to build up a project-specific database for filling the material data space by means of mechanical and analytical material characterisation. In the second casting campaign, a demonstrator cast component was cast at the fem, which was subjected to static bending stress on a laboratory test stand at the IWM. In both casting campaigns, the chemical composition of the AlSi10Mg alloy was varied in terms of the silicon and magnesium content within the scope of the specification.The casting campaigns were accompanied by casting simulations at fem, whose detailed model parameters were fine-tuned by comparing them with temperature measurements in the test rod mould. Various gating systems for the mould of the demonstrator casting were considered and tested using the mould filling simulation at fem. As direct mould filling from above was very uneven and unfavourable due to the resulting turbulence, an ascending casting was preferred. Two variants of this were designed: one with the sprue channel connected to the lower part of the component and one with the use of a so-called knife cut. The latter was selected, with an additional widening of the knife-cut sprue to reduce turbulence during mould filling. In this case, the casts were also carried out with temperature measurements.

Two objectives were pursued: Firstly, all data from the characterisation campaign of the test bars was structured with the help of the developed digital workflow, the data sets of individual process steps were linked with each other and the final coherent knowledge graph of the process chain was transferred to a graph database. Using the domain ontology developed at the IWM for the process chain under consideration, it was possible to show that expert knowledge on the influence of chemical composition and heat treatment parameters on different mechanical properties can be extracted from the material data space. In addition to the retrieval of pure metadata, tensile tests were also used to demonstrate that the heterogeneous raw data sets can be accessed automatically. The material data room technology thus demonstrably represents a future-oriented form of digital knowledge representation of material and process-specific expert knowledge and forms the basis for further data-based analyses. Based on the specific example, decisions can be made regarding the choice of heat treatment parameters depending on the chemical composition in order to achieve a specific material strength. 

Secondly, the demonstrator component was used to show that the integration of a digital twin into simulation and evaluation chains enables more precise statements to be made about the functionality of the component. The twin maps the geometry, the internal material structure, locally varying material properties and characteristic values from the process history and ensures consistency along the process chain under consideration. A graphical user interface was developed at the IWM for the necessary fusion of the material data, which can be used to visualise and correlate locally distributed material and process parameters in a component. 

We would like to thank the Baden-Württemberg Ministry of Economic Affairs, Labour and Housing for funding this project as part of its support for business-related research projects relating to the implementation of the digitalisation strategy in the field of digitalisation: Opportunities for sustainability and the energy transition.

Additive manufacturing of zinc alloys using laser melting

The currently most widely used method of additive manufacturing (AM) of metals is the layer-by-layer exposure of metal powder with a laser. The powder particles are melted, the melt flows together and solidifies into a compact structure. This process is therefore referred to as laser powder bed fusion (LPBF) or laser beam melting (LBM). Various machine manufacturers have coined other terms, although Selective Laser Melting (SLM®) is the most common term in the technical literature and is therefore also used here. 

The first sub-goal of the proposed research project is to explore the possibilities of processing zinc alloys with SLM for prototypes and small series in a cross-industry approach. The mechanical properties, density and corrosion behaviour of SLM test specimens will be compared with corresponding die-cast test specimens. 

One particularly attractive and forward-looking aspect is the use of zinc for SLM-manufactured implants. Zinc is considered to have good bioresorbability, i.e. it has a moderate corrosion rate in vivo and only low cytotoxicity. SLM would make it possible to produce customised implants with specific properties. Suitable bioresorbable Zn-Ag-Au alloys have already been developed as part of an earlier project and analysed in cooperation with the Medical Materials and Technology (MWT) section at the University Hospital of Tübingen.

The IGF project 21472 N of the research association Edelmetalle + Metallchemie is funded by the Federal Ministry for Economic Affairs and Energy via the AiF as part of the programme for the promotion of joint industrial research (IGF) on the basis of a resolution of the German Bundestag.

Innovative Welding Solutions for Aluminium Additive Manufactured Light Weight Components (WeldAlAM)

One of the main cost drivers of today’s lightweight application for automotive or aeronautic components are costs for raw material independent of the manufacturing routes. Complex component designs and large size parts require long lead times and the need of large production infrastructure. With respect to additive manufacturing (AM) of large aluminium parts it becomes increasingly challenging to ensure homogeneous material quality at affordable costs. They can currently not compete with the high and repeatable material quality and low cost structure of semi-finished products such as extrusions and sheets.

AM technology to produce smaller parts and to combine these with semi-finished components offers great potential to overcome the above addressed requirements and high costs for large parts. It opens the opportunity to define interfaces to connect these parts with semi-finished products by industrial well-established joining technologies, such as gas tungsten arc welding (GTAW) or laser beam welding (LBW).

The focus of the WELDALAM project will be on evaluating weldability of high strength aluminium AM parts and consequently validating different welding technologies. The approach will follow a lab-based level to explore process principles and followed by a mock-up phase for two relevant components selected together with the UC.

EB welding represent reference for beam welding and GTAW is intended as basis for conventional arc welding technologies. LBW and friction stir welding will be developed to overcome porosity and weldability problems. The investigation will be covered by non-destructive testing as well as metallographic characterization of the AM parts and weld seams. Additionally surface treatments and corrosion test are planned to qualify the parts for future lightweight applications. SME will benefit from establishing “good practice rules” for different industry sectors, furthermore SME profit from the research regarding surface treated aluminium parts.


Innovative Welding solutions for Aluminium Additive Manufactured light weight components (WeldAlAM) is a Cornet Project funded by national agencies members of the Cornet Network.

Fraunhofer IWS / Dirk Dittrich / +49 351 83391-3228 / dirk.dittrich(at)iws.fraunhofer.de

fem Forschungsinstitut / Dario Tiberto / +49 7171 1006-714 / tiberto(at)fem-online.de

sirris / Olivier Rigo / +32 498 91 94 71 / olivier.rigo(at)sirris.be

CRM Group / Petra Svarova / petra.svarova(at)crmgroup.be