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Electroceramics can be used as:

• Actuators and sensors
• Semiconductors, electrical conductors, ion conductors, insulators, superconductors
• Magnets, control magnetic fields
• Fiber optics
• Voltage and current regulators

There are a wide variety of ceramic materials that have electromechanical, electrochemical, electromagnetic, electro-optic or other electric responses.

The perovskite family of materials are important in many electroceramic applications. Perovskite based ceramics are used in ferroelectric, pyroelectric, piezoelectric, superconductor, thermoelectric, dielectric, magnetic, linear and nonlinear electro-optic devices.

Perovskites in the lead zirconate titanate family (PZT) are ferroelectric (can switch polarization direction) and therefore can be poled in an electric field. Poling aligns the dipoles to give a high piezoelectric response. Piezoelectric means "pressure-electricity". The ceramic will convert a pressure into an electric signal. The converse, or application of an electrical signal, will give a dimensional change in the ceramic. This response is widely used in sensors and actuators and is important in micro-electromechanical systems (MEMS).

Barium titanate is an important perovskite used widely in capacitors in many electronic devices. Layer structure perovskites from the Aurivillius family are finding applications at temperatures where other sensors lose their piezoelectric response, and are also under investigation for other useful properties.

Cubic zirconia has been used as an oxygen sensor to increase fuel efficiency for many years. Recently ceramic oxygen conductors have a new role in solid oxide fuel cells (SOFC), which have the potential economic impact measured in many billions of dollars (and euros). Zirconia is used as an oxygen electrolyte in SOFCs. Cathode and electrode pastes are typically applied and fired on.

The properties of certain electronic ceramics are derived from the grain boundary region or grain/grain boundary junctions. For example, zinc oxide is used as a current voltage regulator. The non-linear characteristics are due to the formation of Schottky barriers at the grain boundaries.

Ferrites are a group of electromagnetic ceramics that are used in many applications, such as magnets for electric motors, e.g. power seats, windows, and door locks. The magnetic moments in ferrites can be aligned and switched in an electric field. The magnetic moments can be permanently or semi-permanently aligned to function as hard or soft magnets, respectively. The switching property can also be used to re-orient electromagnetic fields.

Electroceramics find applications in automotive, computers, cellular phones, ultrasonic detection, energy conversion and many other industries.

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