High purity alumina is used in diverse engineering applications including electronics industry, wear resistant parts, corrosion resistant parts, chemical processing, translucent enclosures for highly corrosive sodium vapour (high pressure sodium vapour lamps), synthetic gems, oil and gas processing, refractories and a wide variety of industrial applications. The chemical applications to eliminate foaming and as catalyst in many reactions are well-known. Activated alumina is used for high adsorptive capacity as desiccant. Calcined alumina is used for refractory and ceramic industries. Because of extreme hardness (9.0 in Moh's scale), low thermal reactivity, high melting point (above 2040°C), significant thermal conductivity, high heat and shock resistance, good electrical insulation even at elevated temperatures, good chemical inertness and outstanding mechanical properties, calcined alumina (also known as reactive alumina) is extensively used in the industry for wear resistant parts, corrosion resistant parts and in a wide range of electrical and electronic applications. Some of these properties, including its porosity and shrinkage are affected by the residual soda content and the particle size of the material.
Zirconia (ZrO2) is a ceramic material with adequate mechanical properties for manufacturing of medical devices. When a stress occurs on a ZrO2 surface, a crystalline modification opposes the propagation of cracks. Compression resistance of ZrO2 is about 2000 MPa. Orthopedic research led to this material being proposed for the manufacture of hip head prostheses.
Boron Nitride is an advanced synthetic ceramic material available in solid and powder form. Its unique properties – from high heat capacity and outstanding thermal conductivity to easy machinability, lubricity, low dielectric constant and superior dielectric strength – make boron nitride a truly outstanding material. In its solid form, boron nitride is often referred to as "white graphite" because it has a microstructure similar to that of graphite. However, unlike graphite, boron nitride is an excellent electrical insulator that has a higher oxidation temperature. It offers high thermal conductivity and good thermal shock resistance and can be easily machined to close tolerances in virtually any shape. After machining, it is ready for use without additional heat treating or firing operations.
