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Thomas R Shrout - One of the best experts on this subject based on the ideXlab platform.

  • investigation of ca3taga3si2o14 Piezoelectric Crystals for high temperature sensors
    Journal of Applied Physics, 2011
    Co-Authors: Shujun Zhang, Lifeng Qin, Xian Zhao, D R Yuan, Qingming Wang, Thomas R Shrout
    Abstract:

    The dielectric and electromechanical properties of fully ordered Ca3TaGa3Si2O14 (CTGS) Crystals were investigated over the temperature range of −60∼700 °C. The highest electromechanical coupling factor, k26 (18.9%) and Piezoelectric coefficient, d26 (−11.5 pC/N) were obtained for (YXl)-25° cuts. The temperature dependent behavior of resonance frequency (fr) was investigated in single-rotated thickness shear mode (TSM) (YXl)θ cuts (θ = −35°∼10°). The turnover temperatures of resonance frequency were found to increase from 20 °C to 330 °C, as the rotation angle θ varied from −22.5° to −35°. Bulk acoustic wave (BAW) resonators based on Y(−30°) monolithic disks with a fundamental frequency ∼2.87 MHz were fabricated, where the in air mechanical quality factor Q was found to be on the order of 24000 and 10000 at 20 °C and 700 °C, respectively. The high coupling k26, high mechanical Q, and high electrical resistivity (16 MΩ·cm) at 700 °C, together with the near zero TCF characteristics at elevated temperatures, ...

  • Dielectric and electromechanical properties of rare earth calcium oxyborate Piezoelectric Crystals at high temperatures
    IEEE Transactions on Ultrasonics Ferroelectrics and Frequency Control, 2011
    Co-Authors: Fapeng Yu, Shujun Zhang, Xian Zhao, Qingming Wang, Duorong Yuan, Thomas R Shrout
    Abstract:

    The electrical resistivity, dielectric, and electromechanical properties of ReCa4O(BO3)3 (ReCOB; Re = Er, Y, Gd, Sm, Nd, Pr, and La) Piezoelectric Crystals were investigated as a function of temperature up to 1000°C. Of the studied Crystals, ErCOB and YCOB were found to possess extremely high resistivity (p): p >; 3 × 107 ω.cm at 1000°C. The property variation in ReCOB Crystals is discussed with respect to their disordered structure. The highest electromechanical coupling factor κ26 and Piezoelectric coefficient d26 at 1000°C, were achieved in PrCOB Crystals, with values being on the order of 24.7% and 13.1 pC/N, respectively. The high thermal stability of the electromechanical properties, with variation less than 25%, together with the low dielectric loss (;1500) at elevated temperatures of 1000°C, make ErCOB, YCOB, and GdCOB Crystals promising for ultrahigh temperature electromechanical applications.

  • zero temperature coefficient of frequency crystal cuts in monoclinic ndca4o bo3 3 Piezoelectric Crystals
    Physica Status Solidi-rapid Research Letters, 2010
    Co-Authors: Shujun Zhang, Xian Zhao, D R Yuan, Qingming Wang, Fapeng Yu, Thomas R Shrout
    Abstract:

    The temperature coefficient of frequency (TCF) was investigated in monoclinic NdCa4O(BO3)3 (NdCOB) Piezoelectric Crystals over the temperature range of –140 °C to 200 °C. A zero TCF characteristic was achieved for the (ZXw) 15° crystal cut, with turnover point at 20 °C. The electromechanical coupling k26 and Piezoelectric coefficient d26, in shear vibration mode, were determined to be 25% and 13.5 pC/N, respectively. The zero TCF crystal cut, large coupling factor and high Piezoelectric coefficient, together with a high mechanical quality factor (Q > 10,000), demonstrate NdCOB Crystals promising candidates for bulk acoustic wave resonators over a wide temperature range. (© 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

  • characterization of neodymium calcium oxyborate Piezoelectric crystal with monoclinic phase
    Crystal Growth & Design, 2010
    Co-Authors: Shujun Zhang, Xian Zhao, D R Yuan, Chunming Wang, Thomas R Shrout
    Abstract:

    Piezoelectric Crystals of neodymium calcium oxyborate, NdCa4O(BO3)3 (NdCOB), were grown by the Czochralski technique. The density was measured using the Archimedes method and found to be 3.63 g/cm3, in good agreement with the theoretical value. The thermal properties of NdCOB have been investigated, with the specific heat being on the order of 0.550 J/(g °C). The four thermal expansion coefficients were measured and found to be α11 = 8.12, α13 = 0.680, α22 = 5.96, and α33 = 10.3 (10−6/°C), respectively. The relative dielectric permittivities were determined to be e11T/e0 = 9.90, e22T/e0 = 15.5, e33T/e0 = 10.2, and e13T/e0 = −1.60, respectively, with corresponding low dielectric loss at 100 kHz, being on the order of <0.1%. The complete set of dielectric, elastic, and Piezoelectric constants for NdCOB single Crystals were determined by the resonance method and compared to other oxyborate Crystals ReCa4O(BO3)3 (Re = rare earth), where NdCOB exhibited relatively higher Piezoelectric properties with d13 = −4....

  • growth and high temperature electromechanical properties of ca3nbx3si2o14 x ga and al Piezoelectric Crystals
    Solid State Communications, 2010
    Co-Authors: Shujun Zhang, Yanqing Zheng, Haikuan Kong, Ru Xia, Jun Xin, Thomas R Shrout
    Abstract:

    Abstract Piezoelectric single Crystals of Ca 3 NbX 3 Si 2 O 14 (CNXS, X=Ga and Al) with ordered langasite structure were successfully grown using the Czochralski technique. The structure was analyzed by X-ray powder diffraction, and the lattice parameters for CNAS were found to decrease slightly when compared to CNGS, due to the smaller ion radius of Al. The dielectric, Piezoelectric and electromechanical properties were studied as function of temperature from 30  ∘ C to 900  ∘ C, showing a stable temperature-dependent behavior. Of particular significant is their high mechanical quality factor and electrical resistivity at elevated temperature, demonstrating CNXS Crystals to be promising candidates for high-temperature applications.

Shujun Zhang - One of the best experts on this subject based on the ideXlab platform.

  • high performance Piezoelectric Crystals ceramics and films
    Annual Review of Materials Research, 2018
    Co-Authors: Susan Troliermckinstry, Shujun Zhang, Andrew J Bell, Xiaoli Tan
    Abstract:

    Piezoelectric materials convert between electrical and mechanical energies such that an applied stress induces a polarization and an applied electric field induces a strain. This review describes the fundamental mechanisms governing the Piezoelectric response in high-performance Piezoelectric single Crystals, ceramics, and thin films. While there are a number of useful Piezoelectric small molecules and polymers, the article focuses on inorganic materials displaying the Piezoelectric effect. Piezoelectricity is first defined, and the mechanisms that contribute are discussed in terms of the key crystal structures for materials with large Piezoelectric coefficients. Exemplar systems are then discussed and compared for the cases of single Crystals, bulk ceramics, and thin films.

  • investigation of the crystal growth thickness and radial modes of α bib3o6 Piezoelectric Crystals
    CrystEngComm, 2017
    Co-Authors: Feifei Chen, Lingfeng Kong, Chunlei Wang, Shujun Zhang, Xiulan Duan, Lifeng Qin, Xian Zhao
    Abstract:

    Monoclinic α-BiB3O6 (α-BIBO) Crystals have been actively studied for various applications. In this paper, large size α-BIBO single Crystals were successfully grown by using the top-seeded solution growth method. The thickness extensional (TE) coupling factor kt and radial extensional (RE) coupling factor kp for α-BIBO Crystals were studied. The equation to evaluate the kp value for Piezoelectric Crystals with monoclinic symmetry was deduced based on the internal energy and Piezoelectric equations. For α-BIBO Crystals, the coupling factor kt was found to be on the order of 44.0% at room temperature, while the experimental kp value was determined to be 32.0%, slightly lower than the theoretical value of 33.7%. In addition, the temperature dependence of TE and RE electromechanical properties were studied over the temperature range of 20–600 °C, where kt was found to show minimal temperature variation, while kp shifted from 32.0% at room temperature to 27.5% at 600 °C, with a negative variation of −14%. The above electromechanical properties indicate the potential usage of α-BIBO Crystals for high temperature Piezoelectric devices.

  • high temperature Piezoelectric Crystals reca 4 o bo 3 3 a review
    IEEE Transactions on Ultrasonics Ferroelectrics and Frequency Control, 2014
    Co-Authors: Fapeng Yu, Xian Zhao, Shujun Zhang
    Abstract:

    High-temperature sensors are desirable for structural health monitoring and/or nondestructive evaluation of next-generation turbines, more efficient jet engines, and the furnace components of electrical power plants. Of all the investigated high-temperature Piezoelectric materials, rare-earth calcium oxyborate Crystals ReCa 4 O(BO 3 ) 3 (ReCOB, Re: rare-earth) exhibit attractive advantages for high-temperature Piezoelectric sensing. In this paper, the electroelastic properties of different ReCOB Piezoelectric Crystals are investigated. The crosstalk between various vibration modes are discussed, from which the optimized crystal cuts are achieved. Furthermore, temperature dependences of the electrical resistivity, dielectric, elastic, Piezoelectric, and electromechanical properties of ReCOB Crystals are studied. Finally, the thermal properties, including thermal expansion, specific heat, and thermal conductivity at elevated temperatures are studied and compared with commercially available high-temperature Piezoelectric Crystals.

  • crack propagation testing using a ycob acoustic emission sensor
    Proceedings of SPIE, 2014
    Co-Authors: Joseph A Johnson, Shujun Zhang, Xiaoning Jiang
    Abstract:

    Piezoelectric Crystals are popular for passive sensors, such as accelerometers and acoustic emission sensors, due to their robustness and high sensitivity. These sensors are widespread in structural health monitoring among civil and industrial structures, but there is little application in high temperature environments (e.g. > 1000°C) due to the few materials that are capable of operating at elevated temperatures. Most Piezoelectric materials suffer from a loss of electric properties above temperatures in the 500-700°C range, but rare earth oxyborate Crystals, such as Yttrium calcium oxyborate (YCOB), retain their Piezoelectric properties above 1000 °C. Our previous research demonstrated that YCOB can be used to detect transient lamb waves via Hsu-Nielsen tests, which replicate acoustic emission waves, up to 1000°C. In this paper, YCOB Piezoelectric acoustic emission sensors were tested for their ability to detect crack progression at elevated temperatures. The sensor was fabricated using a YCOB single crystal and Inconel electrodes and wires. The sensor was mounted onto a stainless steel bar substrate, which was machined to include a pre-crack notch. A dynamic load was induced on the bar with a shaker in order to force the crack to advance along the thickness of the substrate. The obtained raw data was processed and analyzed in the frequency domain and compared to the Lamb wave modes that were evaluated in previous Hsu-Nielsen testing for the substrate.

  • High-temperature Piezoelectric Crystals ReCa4O(BO3)3: a review
    IEEE Transactions on Ultrasonics Ferroelectrics and Frequency Control, 2014
    Co-Authors: Fapeng Yu, Xian Zhao, Shujun Zhang
    Abstract:

    High-temperature sensors are desirable for structural health monitoring and/or nondestructive evaluation of next-generation turbines, more efficient jet engines, and the furnace components of electrical power plants. Of all the investigated high-temperature Piezoelectric materials, rare-earth calcium oxyborate Crystals ReCa4O(BO3)3 (ReCOB, Re: rare-earth) exhibit attractive advantages for high-temperature Piezoelectric sensing. In this paper, the electroelastic properties of different ReCOB Piezoelectric Crystals are investigated. The crosstalk between various vibration modes are discussed, from which the optimized crystal cuts are achieved. Furthermore, temperature dependences of the electrical resistivity, dielectric, elastic, Piezoelectric, and electromechanical properties of ReCOB Crystals are studied. Finally, the thermal properties, including thermal expansion, specific heat, and thermal conductivity at elevated temperatures are studied and compared with commercially available high-temperature Piezoelectric Crystals.

Haosu Luo - One of the best experts on this subject based on the ideXlab platform.

  • enhanced Piezoelectric and ferroelectric properties in mn doped na0 5bi0 5tio3 batio3 single Crystals
    Applied Physics Letters, 2009
    Co-Authors: Qinhui Zhang, Yaoyao Zhang, Feifei Wang, Yaojin Wang, Di Lin, Xiangyong Zhao, Haosu Luo, Dwight D Viehland
    Abstract:

    High Piezoelectric and ferroelectric properties have been found in Mn-doped Na0.5Bi0.5TiO3–BaTiO3 single Crystals, which were grown by a top-seeded solution method. The electrical resistivity, dielectric constant, and ferroelectric and Piezoelectric properties were all found to be notably enhanced by Mn. The Piezoelectric constant d33 and electromechanical coupling coefficients kt and k31 were found to be as high as 483 pC/N, 0.56, and 0.40, respectively. These values are much higher than those previously reported for Pb-free Piezoelectric Crystals, demonstrating the real potential for alternative lead-free systems for sensor and Piezoelectric applications.

  • growth optical and electrical properties of pure and mn doped na0 5bi0 5tio3 lead free Piezoelectric Crystals
    Journal of Alloys and Compounds, 2008
    Co-Authors: Hong Liu, Di Lin, Xiangyong Zhao, Weizhuo Zhong, Xiaoming Pan, Xiangping Jiang, Haosu Luo
    Abstract:

    Abstract In this paper, polycrystalline materials of Na 0.5 Bi 0.5 TiO 3 and 1 at.% Mn-doped Na 0.5 Bi 0.5 TiO 3 (abbreviated as NBT and Mn:NBT) were synthesized by solid-state reaction techniques. Single Crystals were successfully grown by using the top-seeded solution growth (TSSG) method, which dimensions are Φ40 mm × 10 mm for pure NBT crystal and Φ30 mm × 10 mm for Mn:NBT crystal. X-ray powder diffraction results show that the as-grown NBT and Mn:NBT crystal all possess the perovskite structure and belongs to the rhombohedral system and their unit cell constants are almost the same with each other, which are a  =  b  =  c  = 3.8825 A, α  =  β  =  γ  = 89.22° for Mn: NBT crystal and a  =  b  =  c  = 3.8858 A, α  =  β  =  γ  = 89.25° for NBT crystal. The cubic crystallization morphology of NBT crystal can be explained by the model of anionic coordination polyhedral growth-units. Room temperature absorption spectra indicates the existence of Mn 3+ ions in the as-grown Mn:NBT crystal. At room temperature, the dielectric constant of 〈0 0 1〉-oriented NBT is 720 at 1 kHz and it decreases to 600 for 〈0 0 1〉-oriented Mn:NBT crystal. The phase transition temperature Tm corresponding to dielectric constants maximum is moderately decreased from 340 °C to 330 °C by Mn doping. Mn substitution in the NBT crystal significantly increases the values of electromechanical coupling factors k t and Piezoelectric constants d 33 , which are 0.24 and 65 pC/N for NBT crystal, 0.52 and 130 pC/N for Mn:NBT crystal, respectively. These results indicate that the Mn substitution in the NBT crystal results in both hardening and softening effects due to the existence of mixed valence states of Mn ions.

Dwight D Viehland - One of the best experts on this subject based on the ideXlab platform.

Di Lin - One of the best experts on this subject based on the ideXlab platform.

  • enhanced Piezoelectric and ferroelectric properties in mn doped na0 5bi0 5tio3 batio3 single Crystals
    Applied Physics Letters, 2009
    Co-Authors: Qinhui Zhang, Yaoyao Zhang, Feifei Wang, Yaojin Wang, Di Lin, Xiangyong Zhao, Haosu Luo, Dwight D Viehland
    Abstract:

    High Piezoelectric and ferroelectric properties have been found in Mn-doped Na0.5Bi0.5TiO3–BaTiO3 single Crystals, which were grown by a top-seeded solution method. The electrical resistivity, dielectric constant, and ferroelectric and Piezoelectric properties were all found to be notably enhanced by Mn. The Piezoelectric constant d33 and electromechanical coupling coefficients kt and k31 were found to be as high as 483 pC/N, 0.56, and 0.40, respectively. These values are much higher than those previously reported for Pb-free Piezoelectric Crystals, demonstrating the real potential for alternative lead-free systems for sensor and Piezoelectric applications.

  • growth optical and electrical properties of pure and mn doped na0 5bi0 5tio3 lead free Piezoelectric Crystals
    Journal of Alloys and Compounds, 2008
    Co-Authors: Hong Liu, Di Lin, Xiangyong Zhao, Weizhuo Zhong, Xiaoming Pan, Xiangping Jiang, Haosu Luo
    Abstract:

    Abstract In this paper, polycrystalline materials of Na 0.5 Bi 0.5 TiO 3 and 1 at.% Mn-doped Na 0.5 Bi 0.5 TiO 3 (abbreviated as NBT and Mn:NBT) were synthesized by solid-state reaction techniques. Single Crystals were successfully grown by using the top-seeded solution growth (TSSG) method, which dimensions are Φ40 mm × 10 mm for pure NBT crystal and Φ30 mm × 10 mm for Mn:NBT crystal. X-ray powder diffraction results show that the as-grown NBT and Mn:NBT crystal all possess the perovskite structure and belongs to the rhombohedral system and their unit cell constants are almost the same with each other, which are a  =  b  =  c  = 3.8825 A, α  =  β  =  γ  = 89.22° for Mn: NBT crystal and a  =  b  =  c  = 3.8858 A, α  =  β  =  γ  = 89.25° for NBT crystal. The cubic crystallization morphology of NBT crystal can be explained by the model of anionic coordination polyhedral growth-units. Room temperature absorption spectra indicates the existence of Mn 3+ ions in the as-grown Mn:NBT crystal. At room temperature, the dielectric constant of 〈0 0 1〉-oriented NBT is 720 at 1 kHz and it decreases to 600 for 〈0 0 1〉-oriented Mn:NBT crystal. The phase transition temperature Tm corresponding to dielectric constants maximum is moderately decreased from 340 °C to 330 °C by Mn doping. Mn substitution in the NBT crystal significantly increases the values of electromechanical coupling factors k t and Piezoelectric constants d 33 , which are 0.24 and 65 pC/N for NBT crystal, 0.52 and 130 pC/N for Mn:NBT crystal, respectively. These results indicate that the Mn substitution in the NBT crystal results in both hardening and softening effects due to the existence of mixed valence states of Mn ions.