Thickness and thermal processing contribution on piezoelectric characteristics of Pb(Zr-Ti)O₃ thick films deposited on curved IN738 using sol–gel technique

Abstract

Lead zirconate-titanate (PZT) thick films of perovskite structure Pb(Zr x Ti 1-x )O 3 were fabricated on the curved surface of IN738 nickel-based supper alloy substrate up to 15 mm thickness using sol-gel deposition technique without polyvinylpyrrolidone. The films were heated at 200 C with 10 wt% excess PbO, pyrolyzed at 400 C, and subsequently annealed at 650 C, 700 C, and 800 C. Au and Pt thin films were deposited as bottom and top electrodes, respectively. PZT films of different thicknesses and thermal treatment conditions were characterized to investigate the effect of process on crystalline phase development, orientation, and microstructure morphology. Thereby, formation of fairly smooth, semi-dense, and crack-free random orientated thick films as well as an increase in the average grain size and stress relaxation was observed as the film thickness increased. Having optimized the coating process, intrinsic and extrinsic dielectric, ferroelectric and piezoelectric properties were measured as a function of the film thickness, orientation, grain size, and domain wall motions to evaluate the remnant polarization (P r ¼ 7.6-17.5 mC/cm 2 ), coercive field (E c ¼ 2.5-4 kV/ cm), permittivity (" r ¼ 276-326), dielectric loss (tan(%) ¼ 2.7-3), and piezoelectric charge coefficient (d 33 ¼ 71-145 pm/ V) of the PZT thick films prepared potentially to be used as high bandwidth 1-5 MHz structural health monitoring transducers.

PZT/PZT and PZT/BiT Composite Piezo-Sensors in Aerospace SHM Applications: Photochemical Metal Organic + Infiltration Deposition and Characterization

“…PZT precursor solution was prepared using lead 2-ethylhexanoate, zirconium 2-ethyl hexanoate, and Ti-isopropoxide in molar ratio Pb:Zr:Ti = 1.1:0.52:0.48 as the precursors. The applied mixing order and synthesis process were the same as proposed in Reference [4,6,7]. Then, hexane solvent was added to the solution to dilute it to 0.4 M. To make the BiT precursor solution of molar ratio Bi:Ti = 4.4:3, bismuth 2-ethylhexanoate was dissolved in hexane as the solvent.…”

“…Piezoelectric thin films have been used vastly as sensors, accelerometers, micro-motors, and many other low-force electromechanical (E/M) applications [1]. However, high-frequency transducers for structural health monitoring and vibration control systems usually require higher thicknesses to convey E/M stimulation loads appropriately [2,3,4,5,6,7,8,9]. Therefore, thin films cannot be applied this way.…”

PZT/PZT and PZT/BiT Composite Piezo-Sensors in Aerospace SHM Applications: Photochemical Metal Organic+Infiltration Deposition and Characterization

“…However, high-frequency transducers for structural health monitoring and vibration control systems usually require higher thickness to convey appropriately E/M stimulation loads. In such cases, there is a need for thick piezoelectric films with more than 10 microns thicknesses [2][3][4][5][6][7][8]. Therefore, thin films cannot be applicable this way.…”

“…To make the BiT precursor solution of molar ratio Bi:Ti=4.4:3, bismuth 2-ethylhexanoate is dissolved in hexane as the solvent. Then titanium isopropoxide is added and the mixture is stirred on the vibrator for 4 hours, as described in[4, 6,7]. Before starting off the coating process, the substrates are washed and shadow masked in square shapes of 10×10mm and 15×15mmusing temperature-resistant Kapton tape.…”

Elimination of thermal instability in precise positioning of Galfenol actuators

“…Terfenol-D [1][2][3][4], Galfenol [5][6] and Permandure [7][8] are widely used as actuation elements in the new generations of actuators [9][10][11] while these materials are widely used in sensors [12,13] and energy saving systems too [14]. Piezoelectric elements like Lead Zirconate Titanate (PZT) have also today numerous applications in electro-mechanical systems such as actuators for medical applications [15][16], health monitoring transducers [17][18][19]. Magnetorheological materials also are suitable for flexible and tactile actuators, however, low speed response can be counted as their drawback [20][21].…”