Piezoelectricity Vs Ferroelectricity-difference between Piezoelectricity and Ferroelectricity
This page compares Piezoelectricity Vs Ferroelectricity and mentions difference between Piezoelectricity and Ferroelectricity.
The term "piezoelectricity: refers to electricity generated using pressure. In other words, Piezoelectricity is the electric charge which accumulates in the certain solid materials when mechanical stress is being applied. The materials include crystals, ceramics and biological matters e.g. DNA, bone etc. The effect of compression is shown in the figure-1.
Direct Piezoelectric Effect: In this type, material will generate electric potential when
mechanical stress is applied. When compression is applied, volume is decreased and
voltage with same polarity as material is produced. This is shown in the figure.
When tension is applied, volume is increased and voltage with opposite polarity
compare to material is produced.
Inverse Piezoelectric Effect: In this type, when E-field is applied to the material, it gets shortens or lengthens which is proportional to the voltage being applied.
The basic equations for piezoelectricity are as follows.
P =D x Stress ... Equation-1
E = Strain/D ... Equation-2
P = Polarization
E = Generated Electric Field
D = Piezoelectric coefficent (in meters/volt)
The term "Ferroelectricity" is the property of certain non-conducting crystals or dielectrics which exhibit spontaneous electric polarization. This polarization can be reversed by applying appropriate electric field. This is shown in the figure-1.
Refer Ferroelectric Vs Piezoelectric for more information on Ferroelectric and Piezoelectric material types used in Piezoelectricty and Ferroelectricity.