Technical ceramics generally comprises ceramic materials and products for technical applications. In literature and practice, terms such as functional ceramics, structural ceramics, engineering ceramics, industrial ceramics, high-performance ceramics and bioceramics are used. Unique classification often is not possible due to overlaps.

Generally, ceramics parts will perform different functions depending on their material, such as alumina (Al₂O₃), zirconia (ZrO₂), mixed oxides or non-oxidic ceramics, such as silicon nitride (Si₃N₄). Depending on requirements, they have electrical, magnetic, dielectric, optical, mechanical or high-temperature-resilient and thermally insulating properties. The possible uses for technical ceramics therefore are enormous and make the material attractive for many applications in many different industries.

Several work steps are necessary to produce technical ceramics: Raw materials selection in powder form, mass preparation, forming, green processing, sintering, final processing and final quality assurance.

Until completion of the ceramic part, different challenges therefore must be met in order to achieve the optimal product. Sintering in an industrial or laboratory furnace gives the ceramic part its specific material properties. Temperatures of 1200°C to 2200°C are needed for this. Sintering often also takes place under defined atmospheres, such as inert gas or with pressure support.

This in turn leads to specific requirements to furnace heating and insulation. Thus, high-temperature furnaces must offer an optimal temperature distribution or homogeneity within the furnace chamber through the right selection of the heating type, insulation material and furnace construction. Depending on application, the heating-up rates and hold times are extremely variable. For example, an electrically heated dental furnace is able to achieve heating-up rates of less than 15 minutes to 1550°C, depending on the quality and size of the molybdenum disilicide heating element (MolyCom^®-Hyper 1800), the process atmosphere (under air), the insulation material (PCW fibre material such as UltraBoard 1750-400P) and the size of the furnace chamber.

The requirements to sintering, and thus to the high-temperature furnace for its production, can be just as individual as the demands to technical ceramics are. Both is to be understood and coordinated.

In order to understand the customer process and its demand, we use, among others, the following questions:

• Which furnace type is used?
• What sort of application (sintering, firing, heat treatment of…) is present?
• What maximum application temperature does the process need?
• Under what process atmosphere is the furnace operated?
• How long is the hold time at the maximum temperature?
• Is it possible that vapours can gas out of the product?
• Are there any requirements to the product's purity?

This information is the basis for optimal product quality for molybdenum disilicide heating elements (MoSi₂) and insulation materials such as boards, formed parts or blankets of polycrystalline alumina wool (PCW).

As an established specialist for high-temperature technology, we supply customised components from the tried and tested standard product for the firing process control to the individual customisation for electric heating or thermal insulation for construction and operation of industrial and laboratory furnaces up to 1800°C. We make use of our many years of experience in many different application industries. Thus, we develop and implement the optimal and at the same time economically efficient solutions together with our customers.

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