Origin of the low piezoelectric coefficient of metal core 0.3Pb(Zn1/3Nb2/3)O3–0.7Pb(Zr,Ti)O3 piezoelectric fibers

• The MPFs’ piezoelectric properties are lower than those of bulk ceramic counterpart.
• The effect of geometrical shape is a main cause of the low-properties.
• The effect of polarization also is the cause of the low-properties of the MPFs.
• There is excellent agreement between the expected and experimental measurements.

The piezoelectric properties of 0.3Pb(Zn1/3Nb2/3)O3–0.7Pb(Zr,Ti)O3 metal-core piezoelectric fibers (0.3PZN–0.7PZT MPFs) (k31 = 0.253, d31 = −120 pC/N) are lower than those of bulk ceramic counterpart (k31 = 0.375, d31 = −195 pC/N). In order to investigate the origin of this discrepancy, geometrical shape effect and polarization were studied. The effect of geometrical shape is a main cause of the decreased piezoelectric properties of the MPF. However, even though the effect of geometrical shape being considered, the piezoelectric properties of the MPF are much lower than expected. After considering the polarization effect, there is excellent agreement between the expected and experimental measurements. The effect of geometrical shape and polarization are the cause of the decreased properties of the MPFs.