Metallkeramiska

Metallkeramiska, often translated as cermets, are composite materials composed of metallic and ceramic phases. The word "cermet" itself is a portmanteau derived from "ceramic" and "metal". These materials are designed to combine the desirable properties of both constituent classes, offering superior performance characteristics compared to either material alone.

Ceramics are typically hard, brittle, and possess high-temperature resistance and chemical stability. Metals, on the other hand, are ductile, tough, and good conductors of heat and electricity. In cermets, the ceramic phase usually provides hardness, wear resistance, and high-temperature strength, while the metallic phase acts as a binder, improving toughness, ductility, and thermal shock resistance.

The microstructure of a cermet is crucial to its properties. It typically consists of ceramic particles dispersed within a continuous or semi-continuous metallic matrix. The interface between the ceramic and metallic phases plays a significant role in the overall performance. Various fabrication methods, such as powder metallurgy, sintering, and hot pressing, are employed to produce cermets.

Cermets find applications in a wide range of demanding environments. They are commonly used in cutting tools due to their excellent hardness and wear resistance, allowing for high-speed machining. Other applications include thermal barrier coatings for gas turbines, wear-resistant components in engines, electrical contacts, and even in some biomedical implants. The specific combination of ceramic and metal components can be tailored to achieve desired properties for a particular application.