Fabrication, Sinterability, and Mechanical Properties of Lead Zirconate Titanate/Silver Composites

Abstract

High-toughness and high-strength lead zirconate titanate (PZT) composites that contain fine silver particles were successfully fabricated at low sintering temperatures. Addition of silver to a PZT matrix did not result in unwanted reaction phases; however, some silver diffused toward the perovskite crystal structure. A small quantity of silver accelerated the sinterability of the PZT composites. The formation of oxygen vacancies due to the partial substitution of silver appeared to enhance the sinterability of the PZT. Fracture toughness depended on the size and degree of sphericity of the silver particles, and SEM observations on crack propagation suggested that the toughening mechanism in the PZT/Ag composites involves crack bridging resulting from the ductile behavior of silver particles. It is proposed that high fracture strength in PZT/1 to 5 vol% Ag composites results from the relaxation of transformationinduced internal stress by the silver particles.

Interdigital sensors and transducers

“…The major disadvantages of PZT are relatively low mechanical properties, temperature dependence, and exhibition of aging when approaching the Curie temperature [72]. Recently, PZT doped with ZrO [73], Ag [74], and oxides [68] have been investigated and shown to exhibit better material properties.…”

Effects of SiC nanofibers addition on microstructure and dielectric properties of lead titanate ceramics

“…Recently, Niihara [12] had reported that small amount of submicro-or nano-scale second phase could largely improve the mechanical properties of ceramic matrix. In the past few years, this composite idea has been applied to some perovskite ferroelectric ceramics such as BaTiO 3 /SiC [13], PZT/SiC [14] and PZT/Ag [15] systems. However, to our knowledge, the fabrication of PT composites reinforced with SiC nanofibers has not been reported so far.…”

New Percolative BaTiO3–Ni Composites with a High and Frequency-Independent Dielectric Constant (εr ≈ 80000)

“…As a result, internal stresses induced during the sintering process can be relaxed. [17] In order to approach the percolation threshold as closely as possible, we have made a series of insulator cermets with varying metal volume concentration, f. Usually only a modest increase is found [8±10] unless the metal concentration is very close to the percolation point. [11] This is because the variation of the dielectric constant in the neighborhood of the percolation threshold is given by the following power law: [6] áeñ…”