Piezoelectric Performance and Hydrostatic Parameters of Novel 2-2-Type Composites

Area of Science:

• Materials Science
• Condensed Matter Physics
• Piezoelectric Materials

Background:

• 2-2-type composites offer tunable piezoelectric properties.
• Relaxor-ferroelectric single crystals, specifically 0.72 Pb(Mg1/3Nb2/3)O3-0.28PbTiO3, are promising piezoelectric materials.
• Understanding structure-property relationships is crucial for optimizing composite performance.

Purpose of the Study:

• To investigate the structure-piezoelectric property relationships in 2-2-type composites.
• To analyze the hydrostatic response of these composites based on relaxor-ferroelectric single crystals.
• To explore the impact of crystallographic orientation and anisotropic elastic properties on piezoelectric coefficients.

Main Methods:

• Utilized single-domain [111]-poled 0.72 Pb(Mg1/3Nb2/3)O3-0.28PbTiO3 single crystals as Type I layers.
• Incorporated 0-3 composites with modified PbTiO3 ceramic inclusions in a polymer matrix as Type II layers.
• Systematically varied crystallographic orientations to determine maximum hydrostatic piezoelectric coefficients (d*h, g*h, e*h) and figures of merit.

Main Results:

• Achieved large hydrostatic parameters: g*h ≈ 300-400 mV·m/N, e*h ≈ 40-45 C/m², and d*h*g*h ∼ 10⁻¹¹ Pa⁻¹.
• Described a novel effect arising from the interplay between anisotropic elastic properties of Type II layers and polarization orientation in Type I layers.
• Demonstrated significant piezoelectric anisotropy (|d*33/d*3f| ≥ 5 or |g*33/g*3f| ≥ 5).

Conclusions:

• The developed 2-2-type composite system exhibits superior hydrostatic piezoelectric properties compared to conventional composites.
• The newly identified effect provides a pathway for further enhancement of piezoelectric performance.
• These findings pave the way for advanced applications requiring high hydrostatic piezoelectric response.