ADVANCED CERAMICS TECHNOLOGIES
SHAPING PROCESSES
dry pressing
isostatic presses
extrude
ceramic injection molding
Micro ceramic injection molding
film casting
3D ceramic printing
CERAMIC PROPERTIES AND SHAPING TECHNICAL CERAMICS
Technical ceramics have a number of unique properties that make them a versatile material for various applications. Here are some important properties:
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High hardness: Technical ceramics have a high hardness and are more resistant to scratches and abrasion than many other materials.
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High Strength: Ceramic is very strong and can withstand high loads.
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Wear Resistance: Ceramic is also very wear resistant, which means it will remain resistant to wear and tear for a long time.
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High Temperature Resistance: Ceramic is very heat resistant and can be used at high temperatures without losing its properties.
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Chemical resistance: Ceramics are resistant to many chemical compounds and can be used in aggressive environments.
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Low Density: Compared to many other materials, ceramic has a low density, making it a lighter material.
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Good Insulation: Ceramic is a good insulator of electricity and heat, making it a suitable material for electronic and thermal insulation applications.
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Biocompatibility: Some types of ceramics are biocompatible and can therefore be used in medical applications.
It is important to note that depending on the type and composition of the technical ceramic, specific properties may vary.
There are several shaping processes for the production of technical ceramics. Some of the most common are:
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Pressing: This is the most commonly used shaping process for technical ceramics. The powdery raw material is pressed into a mold to obtain the desired shape.
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Extrusion: In this process, the raw material is forced through a die to form a continuous shape, which is then cut to the desired length.
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Injection molding: This involves mixing the ceramic powder with a binder and injecting it into a mold, similar to the way plastic parts are made.
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Isostatic Pressing: This process is similar to regular pressing, however the raw material is pressed into the mold using fluid pressure. As a result, a higher density is achieved and the end product is stronger.
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Casting: In this process, liquid ceramic is poured into a mold and then left to harden and dry.
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3D printing: Ceramic 3D printing is also becoming increasingly popular. Here, the raw material is built up in layers to obtain the desired shape.
The choice of forming process depends on several factors, including the specific requirements of the application, the desired shape and size of the end product, and the production equipment available.
We would be happy to support you in realizing your parts with this process.
DRY PRESSING
Dry pressing is a commonly used shaping process for the manufacture of technical ceramics. This process is also known as uniaxial pressing. With dry pressing, the powdery raw material is filled into a mold and pressed at high pressure of up to 500 MPa. The goal is to shape the raw material into a specific shape and achieve high density by tightly compressing the particles.
The dry pressing process begins with the preparation of the ceramic powder. The powder is usually ground in a ball mill or other grinding tool to achieve a uniform particle size. Then the powder is placed in a mold and pressed with a punch that moves perpendicular to the mold movement. The high pressure and vibrations ensure that the powder is compressed and takes on a solid shape.
After pressing, the component is dried to remove excess moisture and avoid cracks or deformation. Then it is fired at high temperature to achieve high density and strength. The exact firing temperature depends on the type of ceramic used.
Dry pressing of engineering ceramics offers a cost-effective way to produce high-density, high-strength parts. However, due to the high pressure and associated equipment costs, this process can be more expensive than other forming methods such as injection molding.
ISOSTATIC PRESSING
Isostatic pressing is another commonly used shaping process for the manufacture of technical ceramics. This process is also known as cold isostatic pressing. In contrast to dry pressing, in which the raw material is pressed into a mold, isostatic pressing compresses the raw material evenly from all sides under high pressure.
In isostatic pressing, the ceramic powder is placed in a flexible mold that contains a liquid that acts as a transfer medium. The mold is placed in a pressure chamber and compressed evenly from all sides under high pressure of up to 600 MPa. This pressure causes the raw material to be pushed into every corner of the mold, achieving high density.
Isostatic pressing of technical ceramics offers a number of advantages over dry pressing. Because the raw material is compressed evenly from all sides, it can be made into complex shapes with thin walls and sharp edges. In addition, components with a higher density and more homogeneous structure can be produced.
However, isostatic pressing of technical ceramics is more expensive than dry pressing due to the equipment needed and the high pressure required.
We would be happy to support you in realizing your parts with this process.
EXTRUDE
Extrusion is another commonly used process for shaping technical ceramics. A ceramic mass is pressed through a die to create a shape. The process is similar to extruding plastics, but the material that is extruded in this case is a ceramic paste.
Extrusion of engineering ceramics begins with the preparation of a mixture of ceramic powder and a liquid binder that acts as a lubricant and improves the consistency of the mixture. The mixture is forced through a screw press, which forms the material into a cylindrical shape. The material is then pushed through a nozzle, which determines the shape of the end product.
There are different types of nozzles that can be used for different shapes and sizes. A typical application of extruded ceramic products is the manufacture of tubes, rods, tiles and other elongated products with complex shapes.
The advantages of the extrusion of technical ceramics are the possibility to produce products with complex shapes and with very high dimensional accuracy. It is also a very efficient process and requires relatively little investment in tools and machinery. Another advantage is the ability to produce large quantities of products in a short time.
A disadvantage of the extrusion of technical ceramics is that the extruded material often has to be subjected to a sintering process in order to achieve the final density and strength.
INJECTION MOLDING
Injection molding is a process used to shape plastics, but there is also a variant of injection molding that is used to make technical ceramics. In the injection molding of technical ceramics, a ceramic suspension consisting of ceramic powder and liquid binders is injected into an injection mold.
The ceramic suspension is injected under pressure into a heated mold where the liquid binder evaporates and holds the ceramic powder together. The result is a semi-finished ceramic form which, after removal from the mold, is sintered to achieve final density and strength.
Injection molding of technical ceramics has the advantage of allowing high production speeds and excellent part reproducibility. It can also produce complex geometries and fine details. Compared to other processes such as dry pressing or isostatic pressing, thinner walls and larger dimensions can also be achieved with injection molding.
However, there are also disadvantages to the injection molding of technical ceramics. The process requires expensive injection molds that have to be specially made for each part. The preparation of the ceramic suspension and the injection molding process are also relatively complex and require a lot of experience and knowledge. In addition, it is difficult to manufacture large parts or parts with high thickness ratios.
Typical injection molded products:
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Textile components such as ceramic thread eyelets
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Machine components such as ceramic coffee grinding discs
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watch industry such as ceramic watch cases or bezels
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Medical technology such as ceramic dental implants and abutments
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and much more...
We would be happy to support you in realizing your parts with this process.
MICRO INJECTION MOLDING
The micro-injection molding of technical ceramics is a special manufacturing process for the production of micro-components made of ceramic materials. The process is similar to plastic injection molding, but has been adapted to use ceramic powders and smaller molds.
The process begins with the production of a ceramic suspension consisting of fine ceramic powders and binders. The suspension is injected into an injection mold that has the shape of the desired part. The mold is then compacted under high pressure to create a dense and homogeneous structure.
After compaction, the injection mold is heated to remove the binder and harden the ceramic structure. The final step is to compact the part in a high temperature sintering process to achieve final strength and density.
This process enables the manufacture of micro components with very fine detail and high accuracy. A wide variety of complex shapes and geometries can be manufactured, including cavities, holes and thin walls. The ceramic components also exhibit high strength, hardness, abrasion resistance and corrosion resistance.
However, this process requires a high level of technical know-how and experience in handling ceramic powders and designing injection molds. The process can also be relatively expensive, especially when producing in small quantities.
Typical micro injection molded products:
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Dental technology such as ceramic bracket
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Bonding industry like smallest wire guides
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watch industry such as ceramic gears
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and much more...
We would be happy to support you in realizing your parts with this process.
3D PRINTING IN CERAMIC
3D-printing is a relatively new process for the production of technical ceramics. There are several 3D printing technologies that can be used to process ceramics, including Stereolithography (SLA), Selective Laser Sintering (SLS), and Binder Jetting.
SLA uses a UV laser to cure liquid resins layer by layer to form a solid structure. This technology is also used to manufacture ceramic parts by mixing ceramic particles into liquid resins. While the resulting parts are not as dense and strong as those made by other processes, this method is a quick way to create prototypes and small series ceramic parts.
SLS, on the other hand, uses a laser to melt and bond thin layers of ceramic powder. The process is repeated until the part is completely built. The resulting parts have higher density and strength than the parts produced by SLA. However, SLS is more expensive and more difficult to manage.
In binder jetting, a layer of ceramic powder is deposited on a platform and a binder is applied to solidify the powder particles in the desired locations. The process is repeated until the part is completely built. The resulting parts are also dense and strong, however fine detail and complex geometries can be difficult to create.
Overall, 3D printing technical ceramics has some advantages, such as the ability to rapidly prototype and the ability to produce complex geometries. However, there are also some challenges, such as cost and limitations in material selection and surface finish.
We would be happy to support you in realizing your parts with this process.
