Properties of [Pb(Zn_1/3Nb_2/3)O₃]_{<italic>x</italic>}– [Pb(Zr_0.48Ti_0.52)O₃]_{(1–<italic>x</italic>)}Ceramics With Low Sintering Temperature and Their 1–3 Piezocomposites

Abstract

In this paper, dense ( x )PZN-( 1-x )PZT ceramics were prepared at sintering temperatures as low as 950 °C with PZN ratios of x=0.4 , 0.5, and 0.6. The 0.4PZN-0.6PZT composition was found to crystallize in the perovskite phase at this sintering temperature without the presence of any other secondary phases. Higher electrical and electromechanical properties were obtained from the 0.4PZN-0.6PZT composition compared with the x=0.5 and x=0.6 counterparts. Dielectric constant, piezoelectric charge coefficient, electromechanical coupling coefficient, and mechanical quality factor of 0.4PZN-0.6PZT were found to be 2608, 477 pC/N, 64.4, and 65, respectively. While the Curie temperature was 140 °C for pure PZN, the Curie temperature was measured as 300 °C for x=0.4 composition. Green PZN-PZT fibers with circular cross section were drawn using alginate gelation method from the 0.4PZN-0.6PZT composition. Dense fibers were obtained after the sintering process, and piezocomposites were prepared with 1-3 connectivity using fibers with an average diameter of 600 [Formula: see text]. Composites with volume fraction of 20 vol% were investigated for passive acoustic sensor applications. Electrical properties of piezocomposites were found to be scalable and compatible with the electrical properties of the bulk composition. The dielectric constant, piezoelectric charge coefficient, and maximum strain value of the PZN-PZT 1-3 piezocomposite were measured as 345, 165 pC/N, and 0.13%, respectively.

Mechanical and electromechanical properties of piezoelectric ceramic fibers drawn by the alginate gelation method

“…During the development of the alginate gelation fiber drawing process in our laboratory and in our previous studies on drawing fibers of various piezoelectric compositions throughout the years, a qualitative correlation between the initial powder characteristics, the details and order of the processing steps with the resultant mechanical and electromechanical properties of the sintered fibers was identified. The ceramic processing method that is used in the fabrication of the fibers is expected to inherently affect the microstructure of the ceramic, which in return controls the mechanical integrity and electrical properties of the piezoceramic fibers.…”

“…In the last decade, we have also developed a new and environment‐friendly method called the alginate gelation fiber drawing process to draw mainly piezoceramic fibers. Lead‐based full and hollow fibers and lead‐free compositions as well as textured piezoceramic fibers have been drawn and their properties were reported.…”