Introduction
Piezoelectric materials with good stabilities and long-term durability under high temperature conditions are urgently needed for using in harsh industrial environments such as petroleum exploration and aerospace industries [[1], [2], [3]]. In geological mining, the working temperature of piezoelectric actuators can even reach up to 500°C [4,5]. PbNb2O6 and PbTiO3 are commonly used single compositions with TC of approximately 570°C and 490°C for these applications, and their good thermal stability makes them well-established candidates for high temperature applications [6,7]. However, the piezoelectric constant below 100pC/N and the preparation difficulty resulting from their negative thermal expansion phenomenon greatly limit the commercial application of PbNb2O6 and PbTiO3 ceramics [6].
Piezoelectric ceramics in the form of solid solutions, such as lead zirconate titanate (PZT), possess excellent piezoelectric properties with d33 of 374pC/N (PZT-5A) at the morphotropic phase boundary (MPB) [8]. However, the working temperature TW range for piezoelectric devices of PZT is below 150°C because of the low Curie temperature, which is not satisfying the high temperature applications. Most recently, Bi-based solid solutions Bi(Me)O3–PbTiO3 (Me=Sc, In, Fe, Y, Yb, etc.) with ABO3 structure have attracted widespread attention due to their ability to achieve outstanding piezoelectric properties (comparable to PZT) or high Curie temperature of up to 600°C by adjusting the type and content of Me elements [9]. Among them, BiScO3-PbTiO3 (BS-PT) possesses both large d33 ∼ 460pC/N and high TC∼450°C at MPB, and the TW of which is above 200°C [10]. (Bi,La)(Ga,Fe)O3-(Pb,Ba)TiO3 (BLGF-PBT) solid solutions have high TC of ∼340°C, and the d33 at MPB achieves about 186pC/N [11]. It is known that Bi(Me)O3–PbTiO3 solid solutions have mixed rhombohedral and tetragonal phases in the vicinity of MPB, exhibiting the large dielectric and piezoelectric constants, but the thermal stability of εr and d33 are poor for these mixed phase ceramics. For example, the variation of εr and d33 of BS-PT-CT ceramics with the coexistence of tetragonal and rhombohedral phases are about Δεr/ΔT ∼72 /℃ and Δd33/ΔT ∼71% /℃ in temperature range of 200–400°C [12].
Studies have shown that introducing the third end member into BF-PT-based solid solutions to form rhombohedral or tetragonal phased ternary ceramics could improve the dielectric and piezoelectric thermal stability of ceramics. For instance, the rhombohedral BiFeO3-0.29PbTiO3-0.05BaZrO3 ceramics and tetragonal BiFeO3-0.37PbTiO3-0.13Ba(Zr,Ti)O3 ceramics display lower variations of d33 (Δd33/ΔT) over a temperature range of 200°C–400°C, with only 1.9% /℃ and 7% /℃, respectively [13,14]. In addition, the variation of the εr for tetragonal BiFeO3-0.33PbTiO3-0.15BaTiO3 ceramics (Δεr/ΔT=2.8 /℃) at 200–400°C is less than that of the mixed phase BiFeO3-0.48PbTiO3-0.2BaZrO3 ceramics (Δεr/ΔT=9.0 /℃) [15,16]. These findings suggest that the thermal stability of single-phase ceramics is superior to that of mixed phase ceramics, likely due to their stable domain configuration and high polarization switching energy [17].
The BF-0.275PT-0.175BZT ceramics exhibit large piezoelectric constant d33 ∼ 220pC/N and Curie temperature TC ∼434°C, while the problem is that Ba2+ and Zr4+ ions weaken the bonding force of Bi/Pb–O and Fe/Ti–O, resulting in low Curie temperature of the ceramics [18,19]. The reduction of BZT content in BF-PT-BZT single-phase ceramics may concurrently improve the TC and thermal stability. In this paper, tetragonal BiFeO3-xPbTiO3-0.1Ba(Zr0.5Ti0.5)O3 ceramics with different PT contents were designed and prepared by the traditional solid-state reaction method to improve the d33, TC and thermal stability. The effects of PT content on the structure, dielectric, ferroelectric, and high-temperature piezoelectric properties were investigated systematically.
Section snippets
Experimental procedure
The ternary ceramics of (0.9-x)BiFeO3-xPbTiO3-0.1Ba(Zr0.5Ti0.5)O3 (BF-xPT-0.1BZT, x=0.29, 0.30, 0.31 and 0.32) were fabricated by the solid-state reaction method. Bi2O3 (99%), Fe2O3 (99%), PbO (99%), TiO2 (99%), BaCO3 (99%) and ZrO2 (99%) were weighed and batched based on the stoichiometric ratio, and then ball milled in polyethylene jar with zirconia balls and ethanol for 24h. The mixtures were dried and then calcined in crucibles at 750°C for 4h. The calcined powders were ball milled
Results and discussion
Fig. 1 displays the room temperature XRD patterns of BF-xPT-0.1BZT ternary ceramics. It is observed that the BF-xPT-0.1BZT ceramics show pure perovskite structure with dominant tetragonal phase without detectable second phases, indicating that BiFeO3, PbTiO3 and Ba(Zr0.5Ti0.5)O3 form the homogeneous solid solutions with various x values. The increasing concentration of PbTiO3 induces an increase in the distance between (001)T and (100)T diffraction peaks and the largest peak separation observed
Conclusions
In summary, BF-xPT-0.1BZT ternary ceramics with high Curie temperature and excellent piezoelectric constant were prepared by the traditional solid-state reaction method. The content of PT has a great influence on the microstructure and electrical properties of BF-xPT-0.1BZT ceramics. The increase of PT content can effectively increase the grain size and tetragonality of BF-xPT-0.1BZT, and c/a is tailored to 1.041at x=0.31. BF-0.31PT-0.1BZT possesses the largest piezoelectric constant d33 of
Declaration of competing interest
The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.
Acknowledgements
This work was supported by the Open Fund of National Key Laboratory of Science and Technology on Underwater Acoustic Antagonizing (Grant No. JCKY2020207CH02), Original exploration project of Shanghai Natural Science Foundation (Grant No. 22ZR1481100), the Young Scientists Fund and National Natural Science Foundation of China (Grant No. 12204300 and 51872180).
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© 2023 Elsevier Ltd and Techna Group S.r.l. All rights reserved.
FAQs
What is the Curie temperature of piezoelectric ceramics? ›
The commercial piezoelectric material PZT possesses a Curie temperature of about 350°C, but has a maximum recommended operation temperature of 150-250°C.
What is the Curie point of ceramics? ›BaTiO3 ceramic dielectric material are the most common, proved dielectric material used in mass production of ceramic capacitors today. Due to its structure, the maximum capacitance value is achieved nearby Curie temperature ~ 125°C.
Which material has highest Curie temperature? ›One of the highest Curie points is 1,121 °C (2,050 °F) for cobalt. Temperature increases above the Curie point produce roughly similar patterns of decreasing paramagnetism in all three classes of materials.
What is the maximum temp for piezo? ›Piezo Transducers: Sensing, Ultrasound
PI HVPZTs have a Curie temperature of 300°C and can be operated up to a max temperature of 150°C and some cases to 200°C (with high temperature option).
above the curie temperature, a ferromagnetic material becomes paramagnetic.
What is the significance of curie constant? ›In physics, unlike other physical constants, the curie constant is a material dependent property. It expresses the relation between the magnetic susceptibility of a material to its temperature. Measured using K.A.T-1.
Why is the Curie temperature important? ›The Curie temperature of magnets is an extremely important factor to consider when looking at industrial magnets for your industry. Each type of magnet has a maximum temperature it can withstand, and if it exceeds that temperature, it will lose magnetic properties entirely.
What is the difference between Curie temperature and critical temperature? ›Curie's temperature is the critical temperature at which certain magnetic materials undergo changes in their corresponding magnetic properties. It is denoted by T_C. It is also known as Curie Point.
What is the Curie temperature of ceramic magnet? ›Ceramic Magnets
They have a maximum operating temperature of approximately 250 degrees Celsius or higher and a Curie temperature of about 450 degrees Celsius. These magnets, however, are not recommended for use in cryogenic applications.
The Curie temperature of anti-ferromagnetic materials is also known as Néel temperature. It got its name in honour of the French physicist Louis Néel who explained anti-ferromagnetism in 1936. The increasing order of Curie temperature in ferromagnetic, anti-ferromagnetic and ferrimagnetic substances.
What are the disadvantages of piezo? ›
One disadvantage of piezoelectric materials is that they cannot be used for truly static measurements. In addition, the piezoelectric materials also show disadvantages in the unfavorable compatibility and poor durability with the concrete structures [71].
How long does piezoelectric last? ›Piezoelectric sensors are solid state sensors with no internal moving parts to wear or fatigue. Mean Time Between Failure (MTBF) analysis for typical industrial sensors predicts a life of 12 years.
What is the effect of temperature on piezoelectric material? ›It is observed that as the temperature increases, the resonant frequency decreases. The resonant frequency of the piezoelectric element is directly proportional to stiffness constant. If the temperature of the piezoelectric element increases, its stiffness decreases, and so the resonant frequency decreases.
What is the Curie temperature for PZT crystal? ›Above a certain temperature (which is called Curie point Θc) of 120°C, the prototype crystal structure is cubic, with Ba2+ ions at the cube corners, O2- ions at the face centres and Ti4+ ion at the body centre, as shown in Fig.
What is the sintering temperature of PZT? ›Pb(Zr,Ti)O3, (PZT) is known to have excellent piezoelectric properties. In general, PZT ceramics is sintered above 1200 °C.
What is the temperature range of piezoelectric sensor? ›Conventional piezoelectric sensing has been applied widely in sensing of vibration, pressure, mass, distance, chemical and bio-sensing, but its operation temperature is usually below 700 °C. Recent development on high-temperature piezoelectric sensing suggests piezoelectric sensing at temperatures close to 1,000 °C.