Glossary of Terms

Materials Properties

Coefficient of thermal expansion

Either volumetric or linear this describes the expansion that occurs with a change in temperature. Volumetric describes the volume change whereas linear describes the change in dimensions.

Dielectric Constant

The relative permittivity of a material. Indicates the ability of a material to store electrical energy when a voltage is applied to it.

Dielectric Loss

This is the proportion of energy that is dissipated within a dielectric material and lost as heat in an electrostatic field.

Dielectric Strength

The minimum electric field that produces breakdown of the insulating properties of the dielectric.

Dissipation Factor

The dissipation factor is a measure of the loss of power that takes place in virtually all dielectric materials, usually in the form of heat. It is expressed as the ratio of the resistive (loss) component of the current to the capacitive component of current, and is equal to the tangent of the loss angle.

Hermetic Seal

Airtight seal.

Loss Factor

This is the product of the Dielectric Loss and the Dielectric Constant of a dielectric material.

Piezoelectric

When mechanical pressure is applied to one of these materials, the crystalline structure produces a voltage proportional to the pressure. Conversely, when an electric field is applied, the structure changes shape producing dimensional changes in the material. The amount of deformation is proportional to the applied electric field and the d33 coefficient of the material.

Porosity

The proportion of the non-solid volume to the total volume of material. 

Materials and products

PZT

a) Piezoelectric Transducer
b) Lead Zirconate Titanate, Pb(Zr,Ti)O3