Electroceramics are ceramic materials that have been specially formulated for specific electrical, electro-magnetic, or optical properties. Their properties can be tailored for operation as insulators, ferroelectric materials, highly conductive ceramics, electrodes as well, as sensors and actuators. Key factors in developing electroceramics include the presence of ionic-covalent bonding; microstructures comprising inorganic crystal compounds and/or amorphous glass in varying proportion; and thermal processing conducted at elevated temperatures.  Electroceramics include dielectric ceramics, ferrites, ferrogarnets, electrorestrictive ceramics, and piezoelectric ceramics. 

Dielectric ceramics are electrical insulators with dielectric strength, dielectric constant and loss tangent values tailored for specific device applications.  They have high electrical resistivity (low electrical conductivity) and high dielectric strength. Dielectric strength is the resistance to electrical breakdown under an applied electric field.

Electroceramics are ceramic materials that have been specially formulated for specific electrical, electro-magnetic, or optical properties. Their properties can be tailored for operation as insulators, ferroelectric materials, highly conductive ceramics, electrodes as well, as sensors and actuators. Key factors in developing electroceramics include the presence of ionic-covalent bonding; microstructures comprising inorganic crystal compounds and/or amorphous glass in varying proportion; and thermal processing conducted at elevated temperatures.  Electroceramics include dielectric ceramics, ferrites, ferrogarnets, electrorestrictive ceramics, and piezoelectric ceramics. 

Dielectric ceramics are electrical insulators with dielectric strength, dielectric constant and loss tangent values tailored for specific device applications.  They have high electrical resistivity (low electrical conductivity) and high dielectric strength. Dielectric strength is the resistance to electrical breakdown under an applied electric field.

Ferrites are ferrimagnetic oxides with dielectric and magnetic properties that are useful for RF and microwave applications. They have a general formula of ABO₃ and include spinel ferrite, hexagonal ferrite and microwave garnets. Spinel ferrites typically have general formula of AB₂O₄.  Iron based ferrites have the general formula MO-Fe₂O₃ where M is a divalent ion such as Fe, Ni, Cu, Mg, Mn, Co, Zn, Li.

Ferrogarnets or rare earth iron garnets have a fairly complex structure with the general formula of (3M₂O₃)C(2Fe₂O₃)A(3Fe₂O₃)D where M is yttria or rare earth ion and (A,C,D) are lattice site.  They include piezoelectric or relaxor (electrostrictive) ceramics such as quartz, lead titanates, lead zirconates, lead zirconate titanates (PZT), barium titanates and magnesium niobates.  Yttrium aluminum garnet or YIG (Y₂Fe₅O₁₂) is a common microwave or ferromagnetic garnet.  Substituting Al for Fe, or combinations of Ho, Dy or Gd for Y in microwave or ferromagnetic garnets can modify electroceramic magnetization levels.

Electrostrictive ceramics are relaxor ferroelectric ceramics. Strain varies quadratically with electric field for an electrostrictor rather than linearly as in a piezoelectric ceramics.  Relaxors exhibit very high dielectric constants ( K > 20,000), diffuse ferroelectric-to-paraelectric phase transitions, and electrostrictive strain vs. electric field behavior.  Electrostrictors excel at high frequencies and very low driving fields and are applied in specialized microactuators.  Electrostrictors display little or no hysteretic loss even at very high frequencies of operation due to the lack of spontaneous polarization.  For transducer applications, electroceramics must operate under a DC bias field to induce piezoelectric behavior. Operation under bias is characterized by field dependent piezoelectric and electromechanical coupling coefficients.  Relaxors exhibit poor temperature stability and they operate best in situations where the temperature can be stabilized to within approximately 10°C.

Piezoelectric electroceramics include quartz ferroelectric ceramics such as perovskite materials,  lead titanates, lead zirconates, lead zirconate titanates (PZT), barium titanates, and barium tantalate. Piezoelectric materials or piezoceramics produce an electrical charge when a load is applied and deformation occurs. These properties make piezoelectric materials useful for pressure or load sensors.  Inversely, piezoelectric materials produce force or deformation when a load is an electrical charge applied.  These properties make piezoceramics useful for microactuators, nanoactuators or piezoelectric motors.