SFB 920:  Multifunctional Filters for Metal Melt Filtration - a Contribution to Zero Defect Materials

• Subject Area: Materials Science and Engineering ; Thermal Engineering/Process Engineering
• Term: from 2011 to 2023
• Website: Homepage
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 169148856

There exists an increasing pressure on the metal making and metal using industry to remove solid and liquid inclusions such as deoxidation products, sulfides, nitrides carbides etc. and thereby improve metal cleanliness. It is well known that size, type and distribution of non-metallic inclusions in metal exert considerable effects on the mechanical properties of the cast products. The vision of this collaborative research centre is to create a new generation of metal qualities via melt filtration with superior mechanical properties for use in light weight structures and high demand construction materials. The aim of the collaborative research centre is an enormous reduction of non metallic inclusions in the metal matrix by the use of intelligent filter materials as well as filter systems with a functionalized filter surface. Especially in the third period a new generation of combined refining filter systems will be the focus. The metal melt comes first in contact with a reactive filter which generates gas bubbles in the melt as well as activates gas bubbles on the surface of the inclusions. As a result a kind of flotation of the inclusions towards the slag on the surface of the melt takes place. Further the high reactivity as well as the gas bubbles contribute to the agglomeration of the fine inclusions to big clusters which flow due to buoyancy forces to the surface of the melt or are filtrated on the surface of active filters, which do not form gas bubbles but provide on their functionalized surfaces the same chemistry as the inclusions for a sufficient adhesion and as a result for a sufficient filtration of the inclusions. With this approach a purification higher than 95 % can be achieved. The modelling is focusing mainly on the several contributions of the gas bubbles and on the in situ formed reactive layers on the surface of the reactive filters as well as they generate codes with respect to the thermomechanical and functional properties of the filters for a 3D-printing of filter structures which are then end shaped with the aid of a robot-assisted flame spraying technique. The flow dynamic conditions in the filter during casting are of great importance for the proper design of the filter macrostructure. A material as well as a flow computer aided micro- and macrostructure filter design based on investigated filtration mechanisms will lead to high purification efficiencies with superior properties – strength, fracture toughness, fatigue- of the cast steel, iron, aluminum and magnesium components. In addition other applications such as the electronic industry via filtration of copper or the thin aluminum foil production will profit from the scientific results. The target for a higher material efficiency and reduction of energy and CO2-emissions is coming closer in the near future.

• DFG Programme: Collaborative Research Centres
• International Connection: United Kingdom

Current projects

• T07 - Separation of non-metallic impurities (dross) from GJS alloys by filtration (Project Heads Szucki, Michal ;  Wolf, Gotthard )
• T08 - Rotation assisted filtration of particle and fiber reinforced Al alloys (Project Heads Szucki, Michal ;  Wolf, Gotthard )
• T09 - Ceramic Hybrid-Filter-Systems for the ESR-Ingot casting (Project Head Aneziris, Christos G. )
• T11 - Improved Filters for Turbulence Control and Start-up without Freezing at Reduced Melt Superheat Temperature (Project Heads Krause, Hartmut ;  Ray, Subashis )
• T12 - Improvement of purity by means of active and reactive filter systems on the example of a non-ferrous metal alloy (Project Heads Charitos, Alexandros ;  Volkova, Olena )
• T13 - Decopperization of steel by Selenium (Project Head Volkova, Olena )

Completed projects

• A01 - Carbon-bonded filter materials and filter structures with active and reactive functional pores (Project Heads Aneziris, Christos G. ;  Gehre, Patrick ;  Volkova, Olena )
• A02 - Oxide based filter materials and filter structures with active and reactive functional pores (Project Heads Aneziris, Christos G. ;  Brachhold, Nora ;  Gehre, Patrick )
• A03 - Thermodynamics of the filter surface and the inclusions (Project Heads Fabrichnaya, Ph.D., Olga ;  Franke, Peter )
• A04 - Thermodynamic properties and interaction of filter materials and inclusions (Project Heads Himcinschi, Cameliu ;  Kortus, Jens )
• A05 - Interface formation in active and reactive filter structures and phase formation after melt filtration (Project Head Rafaja, David )
• A06 - Dynamic generation of interface layers in a Spark Plasma Sintering Device (Project Head Rafaja, David )
• A07 - Removal of iron from secondary aluminum alloys by metal melt filtration (Project Head Leineweber, Andreas )
• B01 - Increase of the filtration efficiency of ceramic deep bed filters by tailoring of adhesion mechanism (Project Head Peuker, Urs )
• B02 - Velocity behavior – Fluid dynamics in composite filter structures (Project Heads Ray, Subashis ;  Trimis, Dimosthenis )
• B03 - Heat transfer processes in composite filter structures (Project Heads Fieback, Tobias ;  Groß, Ulrich ;  Wulf, Rhena )
• B04 - Tailored agglomeration to increase separation efficiency (Project Heads van den Boogaart, Karl Gerald ;  Peuker, Urs ;  Sandfeld, Stefan )
• B05 - Modelling and evaluation of the thermomechanical behaviour of filter materials and filter structures (Project Heads Abendroth, Martin ;  Kiefer, Ph.D., Björn ;  Kuna, Meinhard ;  Roth, Stephan )
• B06 - Melt filtration in continuous casting operations – continuous casting of steel (Project Heads Bauer, Katrin ;  Schwarze, Rüdiger )
• C01 - Registration of the filtration efficiency of active and reactive filter materials in contact with metal melts with the aid of a metal casting simulator (Project Heads Aneziris, Christos G. ;  Volkova, Olena )
• C02 - High-temperature strength and dimensional stability of C-bonded filter materials (Project Head Biermann, Horst )
• C03 - Determination of temperature-dependent fracture and damage mechanical properties of ceramic filter materials from small scale specimen (Project Heads Abendroth, Martin ;  Kiefer, Ph.D., Björn ;  Kuna, Meinhard )
• C04 - Experimental and stochastic investigations of the influence of the inclusions on the fatigue life (Project Heads Biermann, Horst ;  van den Boogaart, Karl Gerald ;  Sandfeld, Stefan ;  Weidner, Anja )
• C05 - Effect of inclusions on temperature and loading rate dependent strength, deformation and failure behavior (Project Head Krüger, Lutz )
• C06 - Determination of the physico-chemical mechanism and the efficiency of reactive filter materials to avoid H2-porosity in aluminum casting and to remove particles and H2 from magnesium melts (Project Heads Scharf, Christiane ;  Stelter, Michael )
• MGK - Module Integrated Research Training Group (Project Heads Aneziris, Christos G. ;  Biermann, Horst )
• S01 - Sample preparation, filter efficiency and computer tomography (Project Heads Aneziris, Christos G. ;  Hubálková, Jana ;  Rafaja, David )
• S02 - VR-based visual analysis of filtration processes (Project Heads Jung, Bernhard ;  Trimis, Dimosthenis )
• S03 - Active and reactive filtration of steel- and aluminum-melts during the dead mould casting of thin – and thick wall components (Project Heads Eigenfeld, Klaus ;  Keßler, Andreas ;  Wolf, Gotthard )
• T01 - Cleanness of molten steel (Project Heads Aneziris, Christos G. ;  Schwarze, Rüdiger )
• T02 - Determination of fatigue lives and origin of crack initiation of steel piston alloys in the VHCF regime at elevated temperatures (Project Heads Biermann, Horst ;  Weidner, Anja )
• T03 - Deposition of iron-containing intermetallic phases from aluminum alloys by filtration (Project Heads Keßler, Andreas ;  Wolf, Gotthard )
• T04 - Functionalized feeders, hollowware, spider bricks and starter casting tubes for increasing the purity in steel casting processes – Carbon-containing functional coatings and flame-sprayed filter components – (Project Heads Aneziris, Christos G. ;  Gehre, Patrick )
• T05 - Increase in purity of aluminum melts by applying the principle of pre-coat and body feed filtration using encapsulated ceramic deep-bed filters and ceramic fibers (Project Head Peuker, Urs )
• Z - Management and secretary’s office (Project Head Aneziris, Christos G. )

• Applicant Institution: Technische Universität Bergakademie Freiberg
• Spokesperson: Professor Dr.-Ing. Christos G. Aneziris