Electrical Properties of Ceramics and their Applications in Electrical Devices

These flashcards cover key concepts from the lecture on Electrical Properties of Ceramics, including basic electrical principles, applications of ceramics in devices, and characteristics of dielectrics and ferroelectrics.

What law relates current, voltage, and resistance?

Ohm's Law

What is the unit of resistance when the voltage is one volt and the current is one ampere?

1 Ohm

What is the mathematical expression of Ohm's Law?

V = I R (voltage = current x resistance)

What is the term for how easily a material conducts electric current?

Conductivity (σ)

What type of current do ceramic ionic compounds primarily conduct?

Ionic conduction

What determines the total conductivity of an ionic material?

The sum of electronic and ionic contributions

What are dielectric materials used for in electrical applications?

They act as insulators, preventing the flow of electrical charge through them.

What is a key characteristic of ferroelectric materials?

They exhibit spontaneous polarization.

What happens to a dielectric material when subjected to a high enough voltage?

It undergoes dielectric breakdown and becomes a conductor.

What is the Curie temperature in ferroelectric materials?

The temperature at which spontaneous polarization disappears.

What is the role of yttria-stabilized zirconia (YSZ) in oxygen sensors?

YSZ converts oxygen partial pressure to an electrical signal.

What is the effect of doping on ionic conductivity in materials?

Doping introduces vacancies that facilitate ion mobility.

What type of capacitor uses multiple layers of ceramic material interleaved with metal electrodes?

Multilayer Ceramic Capacitors (MLCCs)

What phenomenon explains why some materials can store significantly more charge?

Polarization

What is the relationship between charge density and electric field in dielectric materials?

Polarization increases charge density above vacuum due to the dielectric presence.

What is the significance of electrical conductivity spanning 27 orders of magnitude?

It indicates the broad diversity of conductivity levels in solid materials.