Material Knowledge Ceramics
A family of inorganic non-metallic materials
The term ceramic refers to a variety of inorganic non-metallicMore Information About Ceramics: materials. The ceramics used for industrial purposes are called high-performance ceramics or technical ceramics. Thanks to special and further developed manufacturing processes, high-performance ceramics are used in many branches of mechanical engineering. The advantages of these materials and their possible applications are outlined below.
More Information About Ceramics:
Corrosion resistant
Extreme strength
High temperature resistance
High wear resistance
Different types
Definition of High Performance Ceramics
Ceramics are compounds of metallic and non-metallic elements. The word keramos comes from the Greek and means “potter’s clay”. Ceramics thus refers to both the material and the products made from it.
High-performance ceramics, also called technical ceramics, differ from conventional ceramics by virtue of their precise processing. The secret here lies in the grain structure. A certain grain structure which, due to its purity and grain size, must lie within a defined tolerance range, is decisive for the positive properties.
A synthetically produced ceramic powder brings with it these high requirements for chemical purity and homogeneity that naturally occurring raw materials cannot provide. The resulting variety of high-performance ceramics find use in various branches of mechanical engineering.
Properties of Ceramic
- High wear resistance
- corrosion resistance
- chemical resistance
- no thermal conductivity
- non-magnetic
- high-temperature strength
- extreme strength and dimensional stability
- ductile malleability
- low electrical conductivity
All these special properties of high-performance ceramics are responsible for their prevalence in industry.
High Wear Resistance and Hardness
Ceramics possess an extraordinary hardness compared to other material groups. However, there are differences depending on the structure and type of material.
Hardness testing is carried out using the Vickers (HV) method. In contrast to metallic materials, no plastic deformation occurs in ceramic materials at room temperatures. Nevertheless, a measurable impression is created by the impactor, but this is accompanied by strong radial and lateral cracking.
The ceramic Si3N4 used by us has a Vickers hardness of up to 1700 HV 10. In comparison, the conventional roller bearing steel 100Cr6 is only ca. 700 HV 10.
High Temperature Resistance
- High temperature applications are possible because ceramics retain their strength and rigidity even at high temperatures.
- The thermal conductivity of a material depends on its porosity and grain size. The small interstices and the fact that air is a poor conductor of heat result in the positive property of low thermal conductivity for ceramics.
- The maximum application temperature is determined by the manufacturing process.
High Performance Ceramics Overview
| Übersicht | Produktbeispiel |
|---|---|
| CERAZUR | |
| Z141 | |
| Si3N4 |
Application Fields for High Performance Ceramics
High-performance ceramics are used in many areas where metals and plastics cause problems during processing. The advantages and positive properties of the material are constantly creating new areas of application and a growing sales market.
Chemical, Foodstuff, Pharmaceutical Industries
Special requirements in these industries call for the use of special materials, such as high-performance ceramics. Certain properties, such as resistance to acids and alkalis as well as abrasive substances, enable ceramics to be used in many filters, cladding, fillers, faucets and valves.
The high corrosion resistance and low interaction with other substances rule out undesirable chemical reactions with the workpiece. Impairments of the end product can thus be prevented. Some ceramics meet the hygiene standards specifically required in the foodstuff industry.
An example product is Rest pads, ceramic
Electronics Industries
The electronics industry also requires a particular use of materials due to the special requirements in manufacturing. Sensitive and complex components that need machining and high cycle rates are examples of requirements that call for the use of ceramics.
The plastics that are otherwise often used do not have anywhere near the wear resistance that ceramics bring with them. Another requirement in the electronics industry is the electrical and electromagnetic neutrality of the materials used. One of the many high-performance ceramics can also be used for high-frequency, low-frequency and induction applications.
Automotive Sector
High utilisation of an automated system and the avoidance of downtimes are characteristics of today’s production lines in the automotive industry. The technical challenge here is to achieve the longest possible operating time and service life.
The positive properties of high-performance ceramics, such as extreme strength, high abrasion, corrosion and temperature resistance, increase process reliability and quality. The low wear increases the tool life and reduces the replacement intervals of the components.
An example here is ceramic locating pins. In fixtures with very high exchange intervals and cycle rates, these locating pins compensate for the very high wear. The tool life can thus be increased many times over.