MATERIALS

Silicon carbide consists of the chemical elements silicon (like in sand) and carbon, and is very hard. Due to the good chemical resistance, silicon carbide can be applied very well under extreme conditions.

Due to its crystal structure, silicon nitride is one of the toughest ceramic materials. Furthermore it has a very good thermal shock resistance and good tribological properties.

Aluminum oxide is the most widely applied ceramic type, often used as electrical isolator and for wear-resistant applications. The material is available in several grades.

Of all types of ceramics, the properties of zirconium oxide lie the closest to those of metals. The material is less wear-resistant than e.g. silicon carbide or silicon nitride. On the other hand: zirconium oxide is quite tough and impact resistant.

Of all types of ceramics, the properties of zirconium oxide lie the closest to those of metals. The material is less wear-resistant than e.g. silicon carbide or silicon nitride. On the other hand: zirconium oxide is quite tough and impact resistant.

ZTA and ATZ

By combining aluminum oxide with zirconium oxide on a micron scale, a composite material results with a larger fracture toughness than for aluminum oxide alone.

SIALON

This is a solid solution of aluminum oxide in silicon nitride. In addition to a high strength (also at high temperatures) and a good thermal shock resistance, the material has an extremely good resistance to molten non-ferro metals.

In order to make ceramics tougher and more thermal shock resistant, embedding of ceramic fibres in a ceramic matrix is a solution. Currently, fibres of aluminum oxide and of silicon carbide can be supplied, short as well as long fibres.

Ruby is single-crystal aluminum oxide in which the aluminum ions have been replaced partly by chromium ions. This replacement is the cause of the typical ruby (red) colour. The surface of ruby can be processed very accurately to a material with a beautiful, smooth appearance - the well-known gemstone.