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

  • improving Piezoelectric Property of batio3 catio3 bazro3 lead free ceramics by doping
    Ceramics International, 2014
    Co-Authors: Chunlin Liu, Xiangyong Zhao, Bijun Fang, Xing Liu, Dan Wang, Zhihui Chen, Jianning Ding, Haosu Luo
    Abstract:

    Abstract 1 wt% Li2CO3- or La2O3-doped 0.75BaTiO3–0.15CaTiO3–0.1BaZrO3 (BCZT) lead-free ceramics were prepared by the solid-state reaction method sintered at 1480–1520 °C for 2 h. Sintering temperature, oxide doping and poling electric field influence crystal structure and electrical properties of the sintered BCZT ceramics. Due to oxide doping the BCZT ceramics exhibit pure perovskite structure sintered in a rather wide sintering temperatures with composition locating at the rhombohedral side around the morphotropic phase boundary. The oxide-doped BCZT ceramics exhibit rather homogeneous microstructure morphology, in which grain size of the Li2CO3-doped BCZT ceramics and La2O3-doped BCZT ceramics is around nm-scale and in μm-scale, respectively. Li2CO3 doping increases the value of dielectric constant maximum (em), sharpens the dielectric response peaks and suppresses the dielectric frequency dispersion of the BCZT ceramics, whereas the temperature of em (TC/Tm) changes negligibly. As comparison, La2O3 doping decreases the Tm temperature and enhances dielectric frequency dispersion greatly. The Li2CO3-doped BCZT ceramics exhibit similar P–E hysteresis loop to that of the undoped BCZT ceramics, whereas La2O3 doping deteriorates ferroelectric Property apparently. Li2CO3 doping improves Piezoelectric Property whereas La2O3 doping deteriorates Piezoelectric Property of the BCZT ceramics, which can be interpreted by the formation of different point-charge defects induced by oxide doping.

  • cylindrically shaped ultrasonic linear array fabricated using pimnt epoxy 1 3 Piezoelectric composite
    Sensors and Actuators A-physical, 2013
    Co-Authors: Wei Wang, Qingwen Yue, Yaoyao Zhang, Jie Jiao, Bo Ren, Di Lin, Chung Ming Leung, Xiangyong Zhao, Haosu Luo
    Abstract:

    Abstract In order to improve the flexibility of Pb(In1/2Nb1/2)O3–Pb(Mg1/3Nb2/3)O3–PbTiO3 (PIMNT) single crystal and make full use of the ultrahigh Piezoelectric Property in focused ultrasonic transducers, PIMNT/epoxy 1-3 composite with a volume fraction of 60% was prepared by a modified dice-and-fill method. Excellent properties for ultrasonic transducer applications have been achieved, such as higher thickness electromechanical coupling coefficient (kt = 84%), lower acoustic impedance (Z = 19 MRayls), and moderate dielectric constant ( e 33 T / e 0 = 2040 ). Based on the improved flexibility of as-prepared PIMNT/epoxy 1-3 composite, a cylindrically shaped ultrasonic linear array has been designed, fabricated, and characterized. The cylindrically shaped ultrasonic linear array has achieved an ultra-broad bandwidth (−6 dB) of 128%, which is a significant improvement over the plane linear array. These promising results show that the PIMNT/epoxy 1-3 composite can be used to develop high-performance focused ultrasonic transducers.

  • effect of poling field and temperature on dielectric and Piezoelectric Property of 001 oriented 0 70pb mg1 3nb2 3 o3 0 30pbtio3 crystals
    Materials Research Bulletin, 2006
    Co-Authors: Zuyong Feng, Xiangyong Zhao, Haosu Luo
    Abstract:

    Abstract Effect of poling conditions (different poling fields and temperatures) on dielectric and Piezoelectric Property of 〈0 0 1〉-oriented 0.70Pb (Mg 1/3 Nb 2/3 )O 3 –0.30PbTiO 3 crystal was investigated. The results show, that it is easy for the crystal to be full poled in high temperature, while it is difficult for the crystal in low temperature. An appropriate poling condition for the crystals is suggested.

  • orientation dependence of transverse Piezoelectric properties of 0 70pb mg1 3nb2 3 o3 0 30pbtio3 single crystals
    Applied Physics Letters, 2004
    Co-Authors: Jue Peng, Di Lin, Haosu Luo, Weiqing Jin
    Abstract:

    In this letter, we present our investigation of transverse Piezoelectric performance in 0.70Pb(Mg1∕3Nb2∕3)O3-0.30PbTiO3 (0.70PMN-0.30PT) single crystals with different cuts using a resonance technique. We give the report on the finding of ultrahigh k31 and d31 values of 95.4% and −2517pC∕N, respectively. However, this unusual transverse Piezoelectric Property is only obtained in crystals with the polarization (thickness) and vibration (length) directions along the ⟨110⟩ and ⟨001⟩ directions, respectively. The 0.70PMN-0.30PT crystal with this cut shows significantly great potential for applications in high-performance transverse-mode Piezoelectric devices, such as medical array ultrasonic transducers and actuators.

  • dielectric and Piezoelectric performance of pmn pt single crystals with compositions around the mpb influence of composition poling field and crystal orientation
    Materials Science and Engineering B-advanced Functional Solid-state Materials, 2002
    Co-Authors: Xiangyong Zhao, Bijun Fang, Hu Cao, Yiping Guo, Haosu Luo
    Abstract:

    Abstract This paper presents a detailed study of the dependence of the dielectric and Piezoelectric performance on the composition, poling field and crystallographic direction for Pb(Mg 1/3 Nb 2/3 )O 3 PbTiO 3 (PMN–PT) single crystal plates with compositions around the rombohedral–tetragonal morphotropic phase boundary (MPB). The Tmax of the plates lies in the range of 130–160 °C. Influence of poling field in a range of 0–3 kV mm −1 on their properties was investigated. Under appropriate poling conditions and with proper compositions, the plates show excellent Piezoelectric Property with d 33 larger than 1800 pC N −1 along 〈001〉 and 〈011〉, and 1300 pC N −1 along 〈111〉, respectively. It is also suggested that the relaxor nature of PMN, the domain structure modulation and the MPB effect all play important roles in influencing the Piezoelectric performance. The possibility of the existence of the induced orthorhombic or monoclinic phase is also discussed in this paper.

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

  • Piezoelectric Ceramics with High Piezoelectricity and Broad Temperature Usage Range
    Journal of Materiomics, 2020
    Co-Authors: Qinghu Guo, Fangquan Xia, Pengbin Wang, Xiaoyi Gao, Hua Hao, Hanxing Liu, Huajun Sun, Shujun Zhang
    Abstract:

    ABSTRACT There is a general observation that the Curie temperature and Piezoelectric Property of the ferroelectric ceramics can be enhanced only at the expense of each other, i.e., higher Piezoelectricity, lower Curie temperature, thus, limits their applications over broad temperature range. In this research, Sm-modified 0.15Pb(Mg1/3Nb2/3)O3-(0.85-x)PbZrO3-xPbTiO3 ceramics have been studied, where excellent Piezoelectric coefficients d33 = 720 pC/N, d33*= 950 pm/V and high Curie temperature TC = 293 °C were simultaneously achieved for x = 0.42 composition by designing the morphotropic phase boundary (MPB) with local structural heterogeneity. Of particular significance is that a high thermal stability was observed with Piezoelectric variation below 20% with temperature up to 280 °C, demonstrating that the x = 0.42 composition is a good candidate for Piezoelectric application over broad temperature range where high temperature stability is required. This work provides a good paradigm for designing high-performance Piezoelectric ceramics with high thermal stability via a combination of MPB and local structural heterogeneity.

  • domain configuration and thermal stability of k0 48na0 52 nb0 96sb0 04 o3 bi0 50 na0 82k0 18 0 50zro3 piezoceramics with high d33 coefficient
    ACS Applied Materials & Interfaces, 2016
    Co-Authors: Jialiang Zhang, Chaojing Lu, Shujun Zhang
    Abstract:

    The domain configuration of lead-free (K0.48Na0.52)(Nb0.96Sb0.04)O3–Bi0.50(Na0.82K0.18)0.50ZrO3 ceramics with rhombohedral–tetragonal morphotropic phase boundary, accounting for the high Piezoelectric Property and good thermal stability, were systematically studied. Short domain segments (before poling) and long domain stripes with wedge-shaped or furcated ends (after poling) were found to be typical domain configurations. The reduced elastic energy, lattice distortion, and internal stress, due to the coexistence of rhombohedral and tetragonal phases, result in much easier domain reorientation and domain wall motion, responsible for the high Piezoelectric properties, being on the order of 460 pC/N, in which the extrinsic contribution from irreversible domain switching was estimated to be around 50% of the total Piezoelectricity. Minor Piezoelectric Property variations (<6% over a temperature range from −50 to 100 °C) were observed as a function of temperature, showing a good thermal stability. In addition...

  • fabrication and Piezoelectric Property of batio3 nanofibers
    Journal of the American Ceramic Society, 2014
    Co-Authors: Yongyong Zhuang, Guang Yang, Yaodong Yang, Shujun Zhang
    Abstract:

    BaTiO3 (BTO) nanofibers were fabricated by sol–gel combined with electrospinning method. The effects of the concentration of acetic acid and sintering temperatures on the crystal phase and microstructure of the samples were investigated by scanning electron microscopy, X-ray diffraction, and transmission electron microscopy (TEM). BTO nanofibers with improved surface morphology were obtained as the ethanol to acetic acid ratio (E/A) was 8:3. The fibers calcined at 750°C for 2 h exhibited good morphology and crystallization. TEM studies revealed that the BTO nanofibers were polycrystalline, with diameters being on the order of hundreds nanometer, where the existence of domains offered proof of ferroelectric structure. The ferroelectric domains and piezoresponse of BTO nanofibers were characterized by piezoresponse force microscopy. The calculated d33 was 20 pm/V at maximum strain amplitude.

  • Piezoelectric Property and strain behavior of pb yb0 5nb0 5 o3 pbhfo3 pbtio3 polycrystalline ceramics
    Journal of the American Ceramic Society, 2013
    Co-Authors: Shujun Zhang, Hua Tang, Yujun Feng, Thomas R Shrout
    Abstract:

    (1−x)Pb(Hf1−yTiy)O3–xPb(Yb0.5Nb0.5)O3 (x = 0.10–0.44, y = 0.55–0.80) ceramics were fabricated. The morphotropic phase boundary (MPB) of the ternary system was determined by X-ray powder diffraction. The optimum dielectric and Piezoelectric properties were achieved in 0.8Pb(Hf0.4Ti0.6)O3–0.2Pb(Yb0.5Nb0.5)O3 ceramics with MPB composition, where the dielectric permittivity er, Piezoelectric coefficient d33, planar electromechanical coupling kp, and Curie temperature Tc were found to be on the order of 1930,480 pC/N, 62%, and 360°C, respectively. The unipolar strain behavior was evaluated as a function of applied electric field up to 50 kV/cm to investigate the strain nonlinearity and domain wall motion under large drive field, where the high field Piezoelectric d33* was found to be 620 pm/V for 0.82Pb(Hf0.4Ti0.6)O3–0.18Pb(Yb0.5Nb0.5)O3. In addition, Rayleigh analysis was carried out to study the extrinsic contribution, where the value was found to be in the range 2%–18%.

  • Piezoelectric Property of relaxor pbtio3 crystals under uniaxial transverse stress
    Applied Physics Letters, 2013
    Co-Authors: Shujun Zhang, Samuel Taylor, Jun Luo, Richard J Meyer
    Abstract:

    Strain behavior and Piezoelectric properties of relaxor-PbTiO3 based crystals have been studied under the combination of electric field and static uniaxial transverse compressive stress. The transverse Piezoelectric coefficient, d32, for crystals well into the rhombohedral phase was found to increase with increasing stress due to a morphotropic phase boundary (MPB) effect, while the values for crystals with MPB composition exhibit a contrary trend that is associated with the phase transformation. In addition, an ac drive field was found to depolarize the crystals under stress. Of particular significance is that manganese-modified crystals show stable Piezoelectric properties under ac drive field and stress, which has potential for transducer applications.

Jingfeng Li - One of the best experts on this subject based on the ideXlab platform.

  • further enhancing Piezoelectric properties by adding mno2 in agsbo3 modified li k na nb ta o3 lead free piezoceramics
    Journal of the American Ceramic Society, 2016
    Co-Authors: Lei Zhao, Ke Wang, Longtu Li, Jingfeng Li
    Abstract:

    This work investigated the effect of MnO2 addition on the phase structure, microstructure, and electrical properties of AgSbO3-modified (Li,K,Na)(Nb,Ta)O3 (abbreviated as LKNNT-AS) lead-free Piezoelectric ceramics with an optimized composition endowed with a state of two-phase coexistence. A small amount (0.1 wt%) of MnO2 can significantly further enhance the Piezoelectric Property of LKNNT-AS ceramics, whose Piezoelectric constant d33 and converse Piezoelectric coefficient d33* as well as planar electromechanical coupling factor kp reach 363 pC/N, 543 pm/V, and 0.49, respectively. The temperature stability of Piezoelectricity in MnO2-modified LKNNT-AS samples also improved, which is associated with the more uniform and better thermally stable ferroelectric domains that were revealed by piezoresponse force microscopy.

  • high and frequency insensitive converse Piezoelectric coefficient obtained in agsbo3 modified li k na nb ta o3 lead free piezoceramics
    Journal of the American Ceramic Society, 2012
    Co-Authors: Jiajun Zhou, Fu Li, Jingfeng Li, Ke Wang, Xiaowen Zhang, Qingming Wang
    Abstract:

    AgSbO3 was doped into KNN-based lead-free piezoceramics with an optimized composition of Li0.02(Na0.53K0.48)0.98Nb0.8Ta0.2O3 (abbreviated as LKNNT) to further enhance its Piezoelectric Property. The doping of AgSbO3 was found to be effective in reducing the grain sizes, resulting in more uniform microstructure in AgSbO3-doped LKNNT ceramics. AgSbO3 lowers tetragonal-orthorhombic phase transition point (TT-O), but with a more gentle rate as compared with other dopants. A large converse Piezoelectric coefficient d33* up to 598 pm/V under a relatively low electric field of 1 kV/mm was obtained in the LKNNT-5 mol% AgSbO3 composition, whose tetragonal-orthorhombic phase transition point (TT-O) was controlled near room temperature, but its Curie temperature was kept at 235°C. The d33* obtained in the present material is a very high value for nontextured KNN-based ceramics, which is attributed to the polymorphism phase transition effect and “soft” behavior caused by the addition of AgSbO3.

Xiangyong Zhao - One of the best experts on this subject based on the ideXlab platform.

  • improving Piezoelectric Property of batio3 catio3 bazro3 lead free ceramics by doping
    Ceramics International, 2014
    Co-Authors: Chunlin Liu, Xiangyong Zhao, Bijun Fang, Xing Liu, Dan Wang, Zhihui Chen, Jianning Ding, Haosu Luo
    Abstract:

    Abstract 1 wt% Li2CO3- or La2O3-doped 0.75BaTiO3–0.15CaTiO3–0.1BaZrO3 (BCZT) lead-free ceramics were prepared by the solid-state reaction method sintered at 1480–1520 °C for 2 h. Sintering temperature, oxide doping and poling electric field influence crystal structure and electrical properties of the sintered BCZT ceramics. Due to oxide doping the BCZT ceramics exhibit pure perovskite structure sintered in a rather wide sintering temperatures with composition locating at the rhombohedral side around the morphotropic phase boundary. The oxide-doped BCZT ceramics exhibit rather homogeneous microstructure morphology, in which grain size of the Li2CO3-doped BCZT ceramics and La2O3-doped BCZT ceramics is around nm-scale and in μm-scale, respectively. Li2CO3 doping increases the value of dielectric constant maximum (em), sharpens the dielectric response peaks and suppresses the dielectric frequency dispersion of the BCZT ceramics, whereas the temperature of em (TC/Tm) changes negligibly. As comparison, La2O3 doping decreases the Tm temperature and enhances dielectric frequency dispersion greatly. The Li2CO3-doped BCZT ceramics exhibit similar P–E hysteresis loop to that of the undoped BCZT ceramics, whereas La2O3 doping deteriorates ferroelectric Property apparently. Li2CO3 doping improves Piezoelectric Property whereas La2O3 doping deteriorates Piezoelectric Property of the BCZT ceramics, which can be interpreted by the formation of different point-charge defects induced by oxide doping.

  • cylindrically shaped ultrasonic linear array fabricated using pimnt epoxy 1 3 Piezoelectric composite
    Sensors and Actuators A-physical, 2013
    Co-Authors: Wei Wang, Qingwen Yue, Yaoyao Zhang, Jie Jiao, Bo Ren, Di Lin, Chung Ming Leung, Xiangyong Zhao, Haosu Luo
    Abstract:

    Abstract In order to improve the flexibility of Pb(In1/2Nb1/2)O3–Pb(Mg1/3Nb2/3)O3–PbTiO3 (PIMNT) single crystal and make full use of the ultrahigh Piezoelectric Property in focused ultrasonic transducers, PIMNT/epoxy 1-3 composite with a volume fraction of 60% was prepared by a modified dice-and-fill method. Excellent properties for ultrasonic transducer applications have been achieved, such as higher thickness electromechanical coupling coefficient (kt = 84%), lower acoustic impedance (Z = 19 MRayls), and moderate dielectric constant ( e 33 T / e 0 = 2040 ). Based on the improved flexibility of as-prepared PIMNT/epoxy 1-3 composite, a cylindrically shaped ultrasonic linear array has been designed, fabricated, and characterized. The cylindrically shaped ultrasonic linear array has achieved an ultra-broad bandwidth (−6 dB) of 128%, which is a significant improvement over the plane linear array. These promising results show that the PIMNT/epoxy 1-3 composite can be used to develop high-performance focused ultrasonic transducers.

  • effect of poling field and temperature on dielectric and Piezoelectric Property of 001 oriented 0 70pb mg1 3nb2 3 o3 0 30pbtio3 crystals
    Materials Research Bulletin, 2006
    Co-Authors: Zuyong Feng, Xiangyong Zhao, Haosu Luo
    Abstract:

    Abstract Effect of poling conditions (different poling fields and temperatures) on dielectric and Piezoelectric Property of 〈0 0 1〉-oriented 0.70Pb (Mg 1/3 Nb 2/3 )O 3 –0.30PbTiO 3 crystal was investigated. The results show, that it is easy for the crystal to be full poled in high temperature, while it is difficult for the crystal in low temperature. An appropriate poling condition for the crystals is suggested.

  • dielectric and Piezoelectric performance of pmn pt single crystals with compositions around the mpb influence of composition poling field and crystal orientation
    Materials Science and Engineering B-advanced Functional Solid-state Materials, 2002
    Co-Authors: Xiangyong Zhao, Bijun Fang, Hu Cao, Yiping Guo, Haosu Luo
    Abstract:

    Abstract This paper presents a detailed study of the dependence of the dielectric and Piezoelectric performance on the composition, poling field and crystallographic direction for Pb(Mg 1/3 Nb 2/3 )O 3 PbTiO 3 (PMN–PT) single crystal plates with compositions around the rombohedral–tetragonal morphotropic phase boundary (MPB). The Tmax of the plates lies in the range of 130–160 °C. Influence of poling field in a range of 0–3 kV mm −1 on their properties was investigated. Under appropriate poling conditions and with proper compositions, the plates show excellent Piezoelectric Property with d 33 larger than 1800 pC N −1 along 〈001〉 and 〈011〉, and 1300 pC N −1 along 〈111〉, respectively. It is also suggested that the relaxor nature of PMN, the domain structure modulation and the MPB effect all play important roles in influencing the Piezoelectric performance. The possibility of the existence of the induced orthorhombic or monoclinic phase is also discussed in this paper.

Lei Zhao - One of the best experts on this subject based on the ideXlab platform.

  • further enhancing Piezoelectric properties by adding mno2 in agsbo3 modified li k na nb ta o3 lead free piezoceramics
    Journal of the American Ceramic Society, 2016
    Co-Authors: Lei Zhao, Ke Wang, Longtu Li, Jingfeng Li
    Abstract:

    This work investigated the effect of MnO2 addition on the phase structure, microstructure, and electrical properties of AgSbO3-modified (Li,K,Na)(Nb,Ta)O3 (abbreviated as LKNNT-AS) lead-free Piezoelectric ceramics with an optimized composition endowed with a state of two-phase coexistence. A small amount (0.1 wt%) of MnO2 can significantly further enhance the Piezoelectric Property of LKNNT-AS ceramics, whose Piezoelectric constant d33 and converse Piezoelectric coefficient d33* as well as planar electromechanical coupling factor kp reach 363 pC/N, 543 pm/V, and 0.49, respectively. The temperature stability of Piezoelectricity in MnO2-modified LKNNT-AS samples also improved, which is associated with the more uniform and better thermally stable ferroelectric domains that were revealed by piezoresponse force microscopy.

  • enhanced Piezoelectric properties of bi mg1 2ti1 2 o3 modified bifeo3 batio3 ceramics near the morphotropic phase boundary
    Journal of Alloys and Compounds, 2016
    Co-Authors: Lifeng Zhu, Lei Zhao, Boping Zhang, Ning Wang, Xinchao Shi
    Abstract:

    Abstract (0.7- x )BiFeO 3 −0.3BaTiO 3 – x Bi(Mg 1/2 Ti 1/2 )O 3 system was designed to obtain morphotropic phase boundary (MPB) between rhombohedral ( R ) phase and pseudocubic ( PC ) one to enhance the Piezoelectric Property. Their phase structures were investigated by the X-ray diffraction, temperature dependence of dielectric constant e r and Raman spectrum, which revealed that the phase transition exists from R – PC two-phase coexistence at 0.00 ≤  x  ≤ 0.04 to PC -phase at 0.06 ≤  x  ≤ 0.08 at room temperature. Due to coexisting R – PC two phases near MPB region and the improvement of polarization Property, high d 33  = 154 pC/N, k p  = 28.5% and P r  = 16.2 μm/cm 2 were achieved as x  = 0.04. This research revealed the potential of BiFeO 3 –BaTiO 3 –Bi(Mg 1/2 Ti 1/2 )O 3 system as promising lead-free Piezoelectric ceramics with relatively high Curie temperature T C  = 482 °C.