Enhanced mechanical properties in Ag-particle-dispersed PZT piezoelectric composites for actuator applications

• Published in: Materials science & engineering. A, Structural materials : properties, microstructure and processing Structural materials : properties, microstructure and processing, 2008-12, Vol.498 (1), p.272-277
• Main Authors: Zhang, H.L., Li, J.-F., Zhang, B.-P., Jiang, W.
• Format: Article
• Language: English
• Subjects: Condensed matter: structure, mechanical and thermal properties; Deformation and plasticity (including yield, ductility, and superplasticity); Exact sciences and technology; Mechanical and acoustical properties of condensed matter; Mechanical properties of solids; Mechanical property; Microindentation; Modified small punch; Physics; PZT/Ag
• ISSN: 0921-5093; 1873-4936
• DOI: 10.1016/j.msea.2008.07.073

Functional ceramics naturally have inferior mechanical properties. This study shows that incorporating Ag into lead zirconate titanate (PZT) piezoelectric ceramics by co-firing in air at 1200 °C is effective for mechanical property enhancement. The Ag addition has increased the fracture strength σ f from 69 MPa for monolithic PZT to 129 MPa for PZT–15% Ag composite, and increased the corresponding fracture toughness K IC from 1.0 to 2.4 MPa m 1/2. The Vickers hardness H v decreased with increasing Ag concentration, from 3.8 GPa for monolithic PZT to 2.7 GPa for PZT–15% Ag composite. The strength enhancement is attributed to the combined effects of good interface bonding between Ag and PZT, ductile deformation of Ag particles and particle-dispersion strengthening. The fracture toughness enhancement is correlated to crack deflection and crack arrest due to the existence of Ag particle. The enhanced mechanical properties make the PZT/Ag composites promising candidate for piezoelectric actuator applications.