What are the best processes to machine ceramics?
The term "technical ceramics" summarizes various ceramic materials. What is special about them is that their properties are perfectly tailored to the respective technical applications for optimum use.
In addition to purity, relevant distinguishing criteria from utility ceramics, tiles, sanitary objects or similar are, among others, a narrower tolerance of the grain size of the starting materials as well as special manufacturing and firing processes. Technical ceramics are also referred to as industrial ceramics, high-performance ceramics, industrial or engineering ceramics.
Alumina and Co. - a brief introduction to technical ceramics
Technology and science are subject to a continuous process of further development. This development entails ever more sophisticated and intelligent technologies. And this process is also increasingly changing the demands placed on modern materials.
Among ceramic materials, aluminum oxide is the most widely used. It has excellent electrical insulation and brings very good dielectric strength. Thanks to its temperature resistance of up to 1,750 °C, aluminum oxide is ideal for high-temperature applications and for electrical applications.
Among other things, customers of technical ceramics are demanding greater strength to enable material-saving designs. Lighter components are required to realize maximum energy savings. Higher quality stands for greater safety. A longer service life is also desired, because economic efficiency always plays a decisive role in the end.
For a sensible and effective use of technical ceramics, material-appropriate designs and manufacturing methods as well as applications suitable for ceramics are essential prerequisites. It is not enough to simply reproduce a component made of conventional material in detail as a ceramic version.
In order to develop a ceramic series component, the electrical and thermal as well as the mechanical and chemical loads must be taken into account. In order to find the appropriate materials, corresponding key loads are used to filter them out.
The demands on the new ceramic material are high: It must not only meet the analyses of the technical problem. Over its entire lifetime, an appropriate price-performance ratio and, if necessary, a corresponding additional benefit are required. The next step focuses on drawing and feasibility.
In many cases, the required tolerances for all surfaces are comparatively narrow. A distinction between general tolerances, special tolerances for functional surfaces and typical ceramic tolerances is necessary for this.
Sometimes it is necessary to discuss the functional principles and a new design or revision of the assembly. As an experienced ceramic manufacturer, we accompany you all the way.
Programmed for growth: technical ceramics
The superior property of offering maximum load-bearing capacity almost regardless of chemical, mechanical and thermal influences holds great potential. Thermal resilience and high abrasion resistance are the two pillars of the material's triumphant success to date.
Ceramics are not subject to the corrosion that can occur with many metals. Technical ceramics made of erodible silicon nitride as a material for molds and tools are clearly ahead of metal alloys with their significantly higher strength.
A new generation of materials: fiber-reinforced high-performance ceramics
Technical ceramics offer numerous convincing qualities in everyday use - for example, very good biocompatibility in dental implants, hip implants, finger implants, and various implants placed in the body.
Piezoelectricity in sensors and actuators also speak for technical ceramics. In the past, even highly specialized ceramics were affected by a lack of fracture toughness. Important technological advances have long since been made in this area as well.
Ceramic composites and fiber-reinforced ceramics of the latest generation opened the way to new and demanding applications. These include energy conversion and power generation.
Higher efficiency for engines and machines - thanks to ceramic materials
In order to conserve fossil fuels as much as possible, the focus is on increasing efficiency, especially in the field of combustion-based drive technologies. Increasingly high mechanical and thermal load-bearing capacity is required for valves, seals, plain bearings and rotor blades.
Due to their abrasion resistance, ceramic materials have many advantages here. Rotors used in turbines must be able to withstand extreme heat as well as strong mechanical loads over as long a period as possible.
Metal alloys have corresponding thermal susceptibilities, which is why they are no longer suitable for use. This is where fiber-reinforced high-performance ceramics show their strengths and compensate for the already known disadvantage. Compared to traditional materials, the manufacturing costs for special ceramic materials are significantly higher.
In return, they can be used over a longer period thanks to a longer service life and their abrasion resistance. At the same time, these products entail lower maintenance intensity.
The production of technical ceramics
In order to produce a ceramic component that is optimally tailored to your needs and requirements, selected raw materials such as aluminum oxide, zirconium oxide, silicon carbide, silicon nitride and matching manufacturing processes are used.
The powders, the respective shaping and the sintering process together determine the so-called microstructure during the entire and complex manufacturing process. This then also defines the properties of the products.
Qualified manufacturing processes enable consistently high quality. To ensure this, the manufacturing processes and their results and regulations are regularly monitored and routinely recorded.
Two variants of compound preparation
Basically, there are two possibilities for mass preparation:
1. the manufacturer of technical ceramics purchases the raw materials himself.
He carries out the necessary preparation steps himself. For the various shaping processes, it is necessary to provide the appropriate working mixes.
for the various molding processes: Suspensions for casting. Granules are used for molding, and molding compounds for extrusion.
2. in the second option, the ceramics manufacturer obtains masses that are already ready for processing. In this case, the ceramic process begins directly with molding.
Shaping in technical ceramics
For shaping, we compact the powder particles and thus bring them into a coherent shape. The shaped, but still unfired powder aggregate is called a green compact or green body. If necessary, it is still possible to process it before firing. If the corresponding work steps are carried out only after firing, they are significantly more complex and associated with higher costs.
Noticeable textures and density gradients must not occur in the green body. Under certain circumstances, these can become even more pronounced during firing. This results in internal mechanical stresses and deformations. This circumstance must be taken into account in the various forming processes. So-called dry pressing is suitable for mass-produced articles with high dimensional accuracy.
Granules with good flowability are compacted in profiled steel dies. Dry pressing is the most economical solution for high volumes. It is suitable for simple geometries as well as for complicated shapes. We realize components from match head size to tile size. Platelets or small discs can be pressed up to a thickness of 0.8 to 1 mm.
Do you need thinner and flat components? Then the foil casting process is a good choice. For this purpose, a ceramic slip with organic additives is used; it is cast over a roller-driven endless steel belt. With this manufacturing process, we realize typically ceramic parts with a thickness of 0.25 to 1.0 mm.
Corresponding molded parts are suitable for the production of capacitors, multilayer reactions and the like.Technical ceramic injection molding (CIM) has brought about a continuous improvement in the process chain. Correct material selection, mixing and preparation, suitable injection molds, precisely controlled injection parameters and an exact knowledge of the thermal processes ensure high quality and high precision, even for medium and large volumes.
A high degree of automation is achieved with ceramic injection molding, resulting in high reproducibility and consistent results. Short cycle times are realized in injection molding and the handling of the components is simplified. This makes production in large quantities efficient and economical. Keramikspritzguss:
- Textilkomponenten wie Keramik Fadenösen
- Maschinenkomponenten wie Keramik Kaffeemahlscheiben
- Uhrenindustrie wie Keramik Uhrengehäuse oder Lünetten
- Medizintechnik wie Keramik Dentalimplantate und Abutments
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Possible applications of technical ceramics
Since the development of the first technical ceramics, these high-performance materials have experienced a real boom. Proven in a wide range of applications, the materials are being considered for many new applications. For high wear resistance and hardness, good high-temperature stability and high resistance to corrosion, our high-tech materials are the ideal choice.
Combined with a low specific weight, modern ceramics are convincing all along the line. Technical ceramics have long since become an indispensable component of many applications. This applies to industrial and professional applications as well as to applications in the private sector.
Many household appliances would not even function without ceramic insulators. A reliable power supply would be unthinkable without ceramic components. In all areas of electronics, ceramic components and substrates form the basis for various assemblies and many components.
Plant and mechanical engineering, too, can no longer do without the possibilities and advantages of technical ceramics. Here, control and sliding elements ensure perfect functioning without wear and corrosion. Further examples are industrial furnaces in high-temperature technology. Technical ceramics are indispensable as insulation and construction materials.
We are your expert for technical ceramics projects
We are happy to support you throughout the entire process from development to the finished end product. Do you have any questions?
Please contact us. We are at your disposal.
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