Uwe Scheithauer

Fraunhofer Institute for Ceramic Technologies and Systems | IKTS

Binder Jetting (BJT), a powder-based additive manufacturing technology, has been shown to be a fast and reproducible green shaping process for many different metals. Due to its high productivity and versatility in material processing, BJT is gaining increasing importance in the manufacturing sector. It can also be used for the production of WC-Co h...

Binder-jetting (BJT), a sinter and powder-based additive manufacturing technology, is becoming more and more established on the market due to its high productivity and the wide variety of materials it can process. The production of WC-Co based hardmetals is being promoted by well-known hardmetal and powder manufacturers using the BJT technology. Wi...

A test specimens suitable for strength testing of additive manufactured ceramics is presented. A specimen consists of 48 test pieces in the form of carefully designed constant moment cantilever beams which are attached to a baseplate.

For several years, researchers have been exploring the use of the binder jetting powder-based additive manufacturing process to produce WC-Co hardmetals. Compared to other additive manufacturing processes, binder jetting has the potential for high-volume production. However, due to the powder-based approach, the resulting green bodies typically hav...

For some years now, the production of WC-Co hardmetals via the powder-based additive manufacturing process binder jetting has been pursued. Compared to alternative AM processes Binder jetting offers the possibility of high production. Due to the powder-based process, the green bodies usually have a low green density, which means that only higher Co...

Thermoplastic 3D printing (T3DP) is a ceramic additive-manufacturing (AM) process that uses a thermoplastic feedstock. During T3DP, parts are manufactured by rapid deposition of micron-sized droplets, which fuse and solidify to form lines that fuse further to form layers. This building logic allows modifying the direction of droplet (and line) depo...

Thanks to the layer-by-layer creation of components, additive manufacturing (AM) processes enable the flexible production of components with highly complex geometries, that were previously not realizable or only with very great effort. While AM technologies are very widespread in the research sector, they have so far only been used industrially in...

Aluminum nitride (AlN) is an excellent material for heat sinks and is used, for example, in high-performance electronics, high-power LEDs and photovoltaics. In order to meet the constantly increasing demands on substrate materials and heat sinks resulting from the permanent increase in power density and resulting heat in electronic components, new...

This study addresses a ubiquitous challenge in powder metallurgy: sintering distortion. Sintering distortion can have various causes. On one hand, external factors such as friction with the sintering support during sintering or temperature gradients in the furnace, and, on the other hand, internal factors such as anisotropic shrinkage due to direct...

Hardness, high mechanical strength, wear and corrosion resistance, for instance, are the most important properties of silicon nitride. Next to technical application, the material becomes more and more important for medical applications, especially for implants and the focus in research for this increase steadily. Up to now, the demands on the geome...

Additive Manufacturing (AM) methods drastically simplify or even enable the fabrication of complex structures such as aerospike nozzles while minimising the number of individual parts. The general advantages of additively manufactured ceramic components lie in their low density combined with high strength as well as chemical and thermal resistance....

In this contribution, an overview is given about the MACARONIS project in which a cold-gas thruster system is developed, aiming for an in-orbit demonstration of a ceramic Additively Manufactured (AM) aerospike nozzle made of alumina (Al2O3). The advantages of AM ceramic components lie for the present application in their low density combined with h...

Advanced ceramics are recognized as key enabling materials possessing combinations of properties not achievable in other material classes. They provide very high thermal, chemical and mechanical resistance and typically exhibit lower densities than metals. These properties predestine ceramics for many different applications, especially those in spa...

Advanced ceramics are recognized as key enabling materials possessing combinations of properties not achievable in other material classes. They are characterized by very high thermal, chemical and mechanical resistance and also usually have a lower density than metals. These properties predestine ceramics for many different applications, especially...

Additive Manufacturing (AM) of high-performance materials is becoming more and more established in the market. Especially the field of technical ceramics shows an increasing need for monitoring the manufacturing process in order to identify defects that can be introduced into the component at an early stage and to remedy them if necessary. Optical...

The additive manufacturing of multi-material components represents an extension of the freedom in the design of parts, in which different properties and functionalities can be combined in one part by adding different materials. For this purpose, the CerAM MMJ technology has been developed at Fraunhofer IKTS since 2014, with which an almost unlimite...

Hybrid designs using different materials enable more efficient and lighter functional parts. Strength, density, thermal performance, heat conduction, oxidation and wear behavior are tailored to local requirements. Within the research project industrial user topics are addressed, which take up different questions in the field of multi-material proce...

Multi-material jetting (CerAM MMJ, previously T3DP) enables the additive manufacturing of ceramics, metals, glass and hardmetals, demonstrating comparatively high solid contents of the processed materials. The material is applied drop by drop onto a substrate. The droplets can be adapted to the component to be produced by a large degree of freedom...

Additive manufacturing (AM) is on everyone’s lips, as previously unknown possibilities arise in the field of shaping. However, AM processes also have their limitations in terms of design freedom and still have some catching up to do compared to conventional processes in terms of realizable component properties and manufacturing costs. By adapting A...

Thin-walled 3D-customized ceramic components can be used, e.g. for inert and thermal resistant housings as well as special surface structured kiln furniture. For manufacturing such components, deep drawing of ceramic green tapes has been used. The technology has been almost not applied for processing of ceramic green tapes. A new approach was devel...

Porous ceramics can be realized by different methods and are used for various applications such as cross-flow membranes or wall-flow filters, porous burners, solar receivers, structural design elements, or catalytic supports. Within this paper, three different alternative process routes are presented, which can be used to manufacture porous ceramic...

Porous ceramics can be realized by different methods and are used for manifold applications, like cross-flow-membranes or wall-flow-filters, porous burners, solar receivers, structural design elements or catalytic supports. Within this paper three different alternative process routes are presented, which can be used to manufacture porous ceramic co...

An additive manufacturing technology is applied to obtain functionally graded ceramic parts. This technology, based on digital light processing/stereolithography, is developed within the scope of the CerAMfacturing European research project. A three-dimensional (3-D) hemi-maxillary bone-like structure is 3-D printed using custom aluminum oxide poly...

Technical ceramics are widely used for industrial and research applications, as well as for consumer goods. Today, the demand for complex geometries with diverse customization options and favorable production methods is increasing continuously. With fused filament fabrication (FFF), it is possible to produce large and complex components quickly wit...

To combine the benefits of Additive Manufacturing (AM) with the benefits of Functionally Graded Materials (FGM) to ceramic-based 4D components (three dimensions for the geometry and one degree of freedom concerning the material properties at each position) the Thermoplastic 3D-Printing (CerAM - T3DP) was developed. It is a direct AM technology whic...

The rapid development of additive manufacturing (AM) technologies enables a radical paradigm shift in the construction of heat exchangers. In place of a layout limited to the use of planar or tubular starting materials, heat exchangers can now be optimized, reflecting their function and application in a particular environment. The complexity of for...

Additive manufacturing processes become more and more important in almost all areas, also for medical implant application. Medical implants made of ceramics are known for their excellent biological compatibility. For increasing the ingrowth of cells into an implant, a function-optimized structure with a defined porosity seems to be advantageous. Ad...

Additive manufacturing technologies offer the possibility of tool-free production of components with extremely complex geometry that cannot be attained by any other shaping technique. In our project we are developing a completely new approach for ceramic multi-material additive manufacturing that will allow series production of customized and multi...

In our study, we investigated the additive manufacturing (AM) of ceramic-based functionally graded materials (FGM) by the direct AM technology thermoplastic 3D printing (T3DP). Zirconia components with varying microstructures were additively manufactured by using thermoplastic suspensions with different contents of pore-forming agents (PFA), which...

In our study we investigated the additive manufacturing (AM) of ceramic-based Functionally Graded Materials (FGM) by the direct AM technology Thermoplastic 3D-Printing (T3DP). Zirconia components with a varying microstructure were additively manufactured by using thermoplastic suspensions with different contents of pore forming agents (PFA) and wer...

Additive manufacturing of polymer, metal and ceramic materials is more and more common. For hardmetals however, little work has been reported so far. Since most additive manufacturing methods are based on melting or lithography-based processes, they cannot be used for hardmetals due to the fact that hardmetals neither completely melt nor that they...

Thermoplastic 3D printing (T3DP) is an additive manufacturing (AM) technology, which can be used for the production of dense single- and especially multi-material components. This becomes possible because of the combination of the precise deposition of small droplets of molten thermoplastic suspensions containing ceramic or metal particles, and a c...

Additive manufacturing (AM) techniques allow the preparation of tailor-made structures for specific applications with a high flexibility in regard to shape and design. The lithography-based ceramic manufacturing (LCM) technology allows the AM of high-performance alumina and zirconia components. There are still some restrictions in regard to possibl...

The advantages of suspension based Additive Manufacturing (AM), e.g. the lithography-based ceramic manufacturing (LCM), are high structural resolution, and compared to other available AM techniques, the manufacturing of dense (>99%) ceramic components with high performance. This novel manufacturing technique permits innovative designs, new types of...

The objective of the presented work is to further introduce a new hybrid shaping technique and develop novel porous, near-net shaped composite structures e.g. for personalized bone replacement materials. The suspension-based additive manufacturing technique lithography-based ceramic manufacturing enables high structural resolution and the manufactu...

For the processing of ceramic green tapes to form 3D components, different technologies are known, for instance lamination to multilayer structures or folding. In the metals and plastics industries, deep drawing is, in addition to bending, a widely known method for reshaping sheet metals and polymers. This technology is not, however, applied for pr...

Thermoplastic 3D printing (T3DP) is an Additive Manufacturing (AM) technology that cannot only be used for producing ceramic, metal or multi-material components, but for the Additive Manufacturing of hard metal or cemented carbide components, too. This is possible because the technology combines the precise deposition of small droplets of molten th...

Our new approach in the field of Additive Manufacturing (AM) — thermoplastic 3D printing (T3DP) — is presented. High-filled ceramic and metal feedstocks, based on thermoplastic binder systems, were used for AM of dense ceramic components and metal-ceramic-composites. Compared to other AM methods, the developed T3DP method has outstanding advantages...

Heterogeneous catalysts or static mixers are widely applied in chemical industry. Regardless the extensive research efforts on the development of new catalyst supports or static mixers with low-pressure drop, the industrial application of such structures is limited to differently shaped extrudates only, especially honeycombs. However, particularly...

The main requirement on kiln furniture is the save support or transport of ceramic products during the thermal processing. Therefore, high compressive strength and high bending strength especially at high temperatures are needed. Thick dense or thick porous ceramic plates are state of the art. However, these structures have a high thermal mass, whi...

The development of ceramic and metal-ceramic components with graded microstructures concerning material or porosity opens new fields of application. Components with different porosities combine different properties in the gradient structure regarding thermal conductivity and capacity, density, mechanical strength, and elastic modulus. Graded micros...

Hochleistungskeramiken findet man heute häufig als kritische Komponente in neuentwickelten Systemen für Zukunftsanwendungen. Die Zuverlässigkeit des gesamten Systems basiert hierbei oft auf der kritischen keramischen Komponente. Für diese oft neuentwickelten keramischen Materialien werden neue Methoden für die Prozesssteuerung, Materialdiagnostik u...

Recently, the so-called freeze-foaming method, for achieving open porous and mainly interconnected foam structures, was combined with the Additive Manufacturing technique Lithography-based Ceramic Manufacturing which provides personalized and complex 3D structures. After a co-sintering step, composite structures, combining the advantages of dense a...

Additive manufacturing (AM) allows the designing of the components oriented to function instead to fabrication. Thus, the possibility for further functionalization and miniaturization is provided. By the combination of different materials in one single AM component the number of degrees of freedom can be increased even further. T3DP allows both: Th...

High-performance ceramics are found today often as a critical component in newly developed systems for future applications. The reliability of the entire system in this case often is based on the critical ceramic component. New methods for process control, material diagnostics and structural health monitoring are required for this often newly devel...

Manufacturing technology for new kiln furniture with a significantly lower density and thermal capacity are presented. Extrusion and tape casting are used as two highly productive technologies to produce different green ceramic pre-products, which are combined and co-sintered to realize kiln furniture. Planar green tapes are laminated with an extru...

In our new approach - thermoplastic 3D printing (3DTP) - high-filled ceramic and metal feedstocks based on thermoplastic binder systems were used to produce metal-ceramic-composites by means of additive manufacturing (AM). The developed AM method has some outstanding advantages compared to other methods. First, the portfolio of applicable materials...

Additive manufacturing (AM) opens new possibilities for functionalization and miniaturization of components in many application fields. Different technologies are known to produce single-or multimaterial components from polymer ceramic or metal. Our new approach - thermoplastic 3D printing - makes it possible to produce metal-ceramic composites. Hi...

New kiln furniture representing a low-cost production technology with a significantly lower density and thermal capacity are presented herein. With this kiln furniture high heating and cooling rates can be realized without any defects resulting from thermal stresses. The improved temperature distribution achieved allows for a reduction in the neces...

In our new approach—thermoplastic 3D printing—a high-filled ceramic suspension based on thermoplastic binder systems is used to produce dense ceramic components by additive manufacturing. Alumina (67 vol%) and zirconia (45 vol%) suspensions were prepared by ball milling at a temperature of about 100°C to adjust a low viscosity. After the preparatio...

Introduction Sample Preparation Results and Discussion Summary Acknowledgment

Ceramic and metallic tubes with a multilayered structure have become more and more important to many applications in refractories or environmental technology. This article introduces a new and promising method to produce multilayered tubes consisting of different materials. Scientist from the Fraunhofer Institut for Ceramic Technologies and Systems...

The notation "functionally graded materials" (FGM) is often used in science for improving thermal shock resistance. Many previous simulations of FGM structures promise a positive effect of decreasing thermal stresses in comparison to homogeneous ones, but a practical usage is often not applicable because of critical simplifications. Therefore, this...

At the Fraunhofer Institute for Ceramic Technologies and Systems the principle of manufacturing of carbon-free refractory components by multilayer technology is investigated. Two different material systems are under investigation: Ca-aluminate/Al 2O 3and MgO-stabilized ZrO 2. The manufacturingof multilayer composites by aqueous ceramic tape technol...

The ceramic tape casting technology is used for the development of carbonless refractory materials. For the tape casting process an aqueous slip of alumina, calcium carbonate and organic binder system is developed. Cellulose fibres and graphite platelets are also added to the ceramic slip to generate an adjusted pore volume after sintering of the c...

Piezoceramic fibers are broadly used for advanced ultrasound transducers and composite sensors and actuators for smart system applications. Different techniques (ALCERU® cellulose spinning technique, extrusion, and polysulfone process) have been developed for fiber fabrication, although there is still an essential need to evaluate the mechanical an...

Die Erfindung betrifft ein Verfahren zur Herstellung einer offenporigen Struktur, die von Fluiden durchströmt werden kann, die so hergestellte Struktur und Verwendungen. Aufgabe Erfindung ist es, eine offenporige Struktur zur Verfügung zu stellen, die von einem Fluid durchströmt und dabei katalytisch beeinflusst werden kann, die auch in sehr kleine...

Piezokeramische Fasern, Faserkomposite und LTCC-Module (Low Temperature Cofired Ceramics) zur Integration in Leichtbaustrukturen. Neben dem Einsatz als Ultraschallwandler sollen die Piezo-Faserkomposite im Rahmen des Teilprojektes A2 des SFB/Transregios 39 in ein Aluminiumblech mittels Umformen eingeprägte Struktur integriert werden, in der nach ei...

The present paper reports on a new module design based on LTCC-PZT laminates. The assembly of modules is achieved by packaging of ceramic PZT plates between LTCC green layers and subsequent sintering of the evolving multilayer. The challenge exists in avoiding tension cracks at shrinking of LTCC layers on the already sintered piezoceramic during th...

To raise the knitting productivity of biaxially reinforced fabrics and to increase the quality, a new fabric take-down system has to be developed. Such a system was constructed by the ITB for the flat knitting machine CMT-211 and for serial production of biaxially reinforced multi-layer fabrics. In this article engineering solutions are suggested.