Dr. Dmitri Kopeliovich
Alumina (aluminum oxide) is the most important, widely used and cost effective oxide ceramic material.
The technical alumina ceramics contain at least 80% of aluminum oxide (AL2O3).
Small amounts of silica (SiO2), magnesia (MgO) and zirconia (ZrO2) may be added to alumina ceramics.
Addition of zirconia to alumina ceramic results in considerable increase of the material fracture toughness.
Alumina possesses strong ionic bonding, which determines the material properties:
Aluminum ceramics parts are manufactured by the following technologies: uniaxial (die) pressing, isostatic pressing, injection molding, extrusion and slip casting. The parts may be machined in "green" condition before sintering (firing).
Aluminum ceramics are widely used in electronics and electrical engineering, metallurgical processes, chemical technologies, medical technologies, mechanical engineering, military equipment.
Aluminum ceramics are used for manufacturing insulators, capacitors, resistors, furnace tubes, sealing refractory parts, foundry shapes, wear pads, thermocouple protection tubes, cutting tools and polishing/grinding powders, ballistic armor, laboratory equipment, bio-ceramic parts for orthopedic and dental surgery, bearings.