Showing papers by "Thomas R. Shrout published in 2010"
TL;DR: The results revealed that the intrinsic (reversible) contribution plays a dominant role in the high piezoelectric activity for PMN-PT crystals, and the extrinsic contribution was found to be less than 5% for the compositions away from R-M(C) and M(C)-T phase boundaries, due to a stable domain engineered structure.
Abstract: The piezoelectric response of [001] poled domain engineered (1−x)Pb(Mg1/3Nb2/3)O3−xPbTiO3 (PMN-PT) crystals was investigated as a function of composition and phase using Rayleigh analysis. The results revealed that the intrinsic (reversible) contribution plays a dominant role in the high piezoelectric activity for PMN-PT crystals. The intrinsic piezoelectric response of the monoclinic (MC) PMN−xPT crystals, 0.31≤x≤0.35, exhibited peak values for compositions close to R-MC and MC-T phase boundaries, however, being less than 2000 pC/N. In the rhombohedral phase region, x≤0.30, the intrinsic piezoelectric response was found to increase as the composition approached the rhombohedral-monoclinic (R-MC) phase boundary. The maximum piezoelectric response was observed in rhombohedral PMN-0.30PT crystals, being on the order of 2500 pC/N. This ultrahigh piezoelectric response was determined to be related to the high shear piezoelectric activity of single domain state, corresponding to an ease in polarization rotation, for compositions close to a morphotropic phase boundary (MPB). The role of monoclinic phase is only to form a MPB with R phase, but not directly contribute to the ultrahigh piezoelectric activity in rhombohedral PMN-0.30PT crystals. The extrinsic contribution to piezoelectric activity was found to be less than 5% for the compositions away from R-MC and MC-T phase boundaries, due to a stable domain engineered structure. As the composition approached MPBs, the extrinsic contribution increased slightly (<10%), due to the enhanced motion of phase boundaries.
229 citations
TL;DR: The results demonstrated that the thickness dependent properties of relaxor-PT ferroelectrics are closely related to the domain size with respect to the associated macroscopic scale of the samples.
Abstract: The electrical properties of Pb(Mg(1/3)Nb(2/3))O(3)-PbTiO(3) (PMN-PT) based polycrystalline ceramics and single crystals were investigated as a function of scale ranging from 500 microns to 30 microns. Fine-grained PMN-PT ceramics exhibited comparable dielectric and piezoelectric properties to their coarse-grained counterpart in the low frequency range ( 40 MHz). For PMN-PT single crystals, however, the dielectric and electromechanical properties degraded with decreasing thickness, while ternary Pb(In(1/2)Nb(1/2))O(3)-Pb(Mg(1/3)Nb(2/3))O(3)-PbTiO(3) (PIN-PMN-PT) exhibited minimal size dependent behavior. The origin of property degradation of PMN-PT crystals was further studied by investigating the dielectric permittivity at high temperatures, and domain observations using optical polarized light microscopy. The results demonstrated that the thickness dependent properties of relaxor-PT ferroelectrics are closely related to the domain size with respect to the associated macroscopic scale of the samples.
108 citations
TL;DR: In this paper, a complete set of elastic, dielectric, and piezoelectric constants of PIN-PMN-28%PT and PIN-MPN-32%PT were measured by using combined resonance and ultrasonic methods.
Abstract: Ternary single crystals xPb(In1/2Nb1/2)O3–(1−x−y)Pb(Mg1/3Nb2/3)O3–yPbTiO3 (PIN-PMN-PT) poled along [011]c showed remarkable electromechanical properties. We report complete sets of elastic, dielectric, and piezoelectric constants of PIN-PMN-28%PT and PIN-PMN-32%PT, measured by using combined resonance and ultrasonic methods. The electromechanical coupling coefficients k15, k32, and k33 can reach 0.95, 0.90, and 0.92, and the piezoelectric strain coefficients d15, d32, and d33 are as high as 3354 pC/N, −1781 pC/N, and 1363 pC/N, respectively. These full matrix data sets provide the base for fundamental studies on domain engineering phenomena as well as urgently needed input data for the design of electromechanical devices using [011]c poled PIN-PMN-PT single crystals.
107 citations
TL;DR: In this article, a high temperature monolithic compression-mode piezoelectric accelerometer was fabricated using YCa4O(BO3)3 (YCOB) single crystals.
Abstract: High temperature sensors are of major importance to aerospace and energy related industries. In this letter, a high temperature monolithic compression-mode piezoelectric accelerometer was fabricated using YCa4O(BO3)3 (YCOB) single crystals. The performance of the sensor was tested as function of temperature up to 1000 °C and over a frequency range of 100–600 Hz. The accelerometer prototype was found to possess sensitivity of 2.4±0.4 pC/g, across the measured temperature and frequency range, indicating a low temperature coefficient. Furthermore, the sensor exhibited good stability over an extended dwell time at 900 °C, demonstrating that YCOB piezoelectric accelerometers are promising candidates for high temperature sensing applications.
94 citations
TL;DR: In this article, lead-free piezoelectric ceramics were prepared by conventional ceramic processing and X-ray diffraction on the samples revealed that Li + ions diffused into the Bi 0.5 Na 0.
Abstract: The piezoelectric and ferroelectric properties of 0.852[Bi 0.5 (Na (1-x) Li x ) 0.5 ]TiO 3 -0.110(Bi 0.5 K 0.5 )TiO 3 -0.038BaTiO 3 (x = 0, 0.02, 0.05, 0.10, 0.15, and 0.30, abbreviated as BNKLBTx) lead-free piezoelectric ceramics were prepared by conventional ceramic processing. X-ray diffraction on the samples revealed that Li + ions diffused into the Bi 0.5 Na 0.5 TiO 3 lattices (A-site) and formed a solid solution with a single perovskite structure. All the samples could be sintered at 1160°-1180°C, with the density being on the order of > 95% of the theoretical. The ceramics with x = 0.10 exhibited the highest properties, with the piezoelectric coefficient being on the order of d 33 = 235 pC/N, while the electromechanical coupling factors were found to be k p = 0.30 and k t = 0.45, respectively. The dielectric, pyroelectric, electromechanical, and ferroelectric behaviors were investigated as a function of temperature. It was found that the depolarization temperature T d showed a strong dependence on the content of Li + addition, shifting to a lower temperature with increasing Li + dopant.
87 citations
TL;DR: In this article, the authors measured a complete set of material properties of single domain PIN-PMN-PT crystal, which is urgently needed in theoretical studies and electromechanical device designs using this crystal.
Abstract: Pb(In(12)Nb(12))O(3)-Pb(Mg(13)Nb(23))O(3)-PbTiO(3) (PIN-PMN-PT) single crystals have been developed recently, which can increase the operating temperature by at least 20 degrees C compared to PMN-PT crystals. We have measured a complete set of material properties of single domain PIN-PMN-PT crystal, which is urgently needed in theoretical studies and electromechanical device designs using this crystal. Because the rotated values of d33*=1122 pCN and k33*=89% along [001](c) calculated using the single domain data obtained here are in good agreement with the [001](c) poled multidomain PIN-PMN-PT crystals, one may conclude that the physical origin of the ultrahigh piezoelectric properties mainly come from orientation effect.
64 citations
TL;DR: The piezoelectric properties of Pb(Mg(13)Nb(23))O(3)-PbTiO( 3) polycrystalline ceramics were found to decrease by 75%, showing both intrinsic and extrinsic contributions play important role in the reduction in piezOElectricity at cryogenic temperatures for ceramic.
Abstract: The piezoelectric activity in [001] poled Pb(In1/2Nb1/2)O3–Pb(Mg1/3Nb2/3)O3–PbTiO3 crystals was investigated as a function of composition and temperature. The level of intrinsic and/or extrinsic contribution to the total piezoelectric activity was analyzed using Rayleigh method. The results revealed that though 95% of the observed piezoelectric activity in rhombohedral crystals was intrinsic (lattice), the properties decreased significantly with decreasing temperature. At −150 °C, the piezoelectric response decreased by 40%–55% for the compositions close to a morphotropic phase boundary (rhombohedral-monoclinic or monoclinic-tetragonal), while decreasing only 20%–30% for the compositions in the rhombohedral region. The piezoelectric properties of Pb(Mg1/3Nb2/3)O3–PbTiO3 polycrystalline ceramics were found to decrease by 75%, showing both intrinsic and extrinsic contributions play important role in the reduction in piezoelectricity at cryogenic temperatures for ceramics.
64 citations
TL;DR: In this article, the 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 Nd COB exhibited relatively higher pyrolyte properties with d13 = −4.
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....
61 citations
TL;DR: In this paper, lead-free piezoelectric ceramics (K0.45Na0.55)NbO3 (KNN) modified by K4CuNb8O23 (KCN) were synthesized using conventional ceramic processing.
Abstract: Lead-free piezoelectric ceramics (K0.45Na0.55)NbO3 (KNN) modified by K4CuNb8O23 (KCN) were synthesized using conventional ceramic processing. All the ceramics possessed the perovskite structure with orthorhombic symmetry. Results revealed that the addition of KCN was effective in enhancing the density of KNN. The addition of KCN was found to slightly decrease To–t and Tc. The coercive field (Ec) was found to maintain the same value by the addition of KCN while the internal bias (Ei) sharply increased to 4 kV/cm with 0.5 mol% KCN. The low migration rate of defect dipoles was correlated with the build-up of Ei, which was responsible for the stabilization of the domain wall and the improvement of Qm. Therefore, KNN–KCN0.5 exhibited excellent piezoelectric properties of d33 (100 pC/N), kp (33%), and Qm (1500), making them promising candidates for applications requiring hard piezoelectrics.
58 citations
TL;DR: In this paper, electric fatigue tests have been conducted on pure and manganese-modified Pb(In 0.5 Nb 0.3 Nb 2/3 )O 3 (PIN-PMN-PT) single crystals along different crystallographic directions.
50 citations
TL;DR: In this article, the orientation-dependent electromechanical properties were calculated for tetragonal Pb(In 1/2Nb1/2)O3-Pb(Mg1/3Nb2/3)O 3 (PIN-PMN-PT) crystals based on single-domain data.
Abstract: The orientation-dependent electromechanical properties were calculated for tetragonal Pb(In1/2Nb1/2)O3–Pb(Mg1/3Nb2/3)O3– PbTiO3 (PIN–PMN–PT) crystals based on single-domain data. The maximum electromechanical couplingwas found to lie along the polar direction [001], whereas the maximum piezoelectric coefficientwas found to occur along [011]. Subsequently, the piezoelectric properties of [011] poled tetragonal PIN–PMN–PT crystals, with an engineered domain configuration (“2T”), were studied using resonance impedance measurement and strain versus electric field (S–E) behavior, where the piezoelectric coefficient d33 and coupling k33 of [011] poled crystals were found to be on the order of 1000 pC/N and 0.75, respectively. The high d33 of [011] poled crystals was associated with the high shear coefficient d15 (∼2300 pC/N) in single domain state. Finally, the piezoelectric and electromechanical properties of [011] domain engineered tetragonal PIN–PMN–PT crystals were investigated as a function of temperature. In contrast to [001] single-domain PIN–PMN–PT crystals, the piezoelectric coefficient d33 and coupling k33 of [011] poled crystals were found to decrease with increasing temperature.
TL;DR: In this article, single-domain PIN-PMN-PT crystals were investigated for temperature and dc bias electric-field characteristics of tetragonal PIN-N-PN-PT crystal, and they exhibited broader temperature usage range and higher thermal/electric field stability.
Abstract: single domain piezoelectric coefficients d33, d15, and d31 were found to be 530, 2350, and 200 pC/N, respectively, with electromechanical coupling factors k33, k15, and k31 being on the order of 0.84, 0.85, and 0.58. The mechanical quality factor Q for longitudinal mode was found to be 700, with high coercive field Ec being on the order of 10 kV/cm. The temperature and dc bias electric-field characteristics of single domain tetragonal PIN–PMN–PT crystals were also investigated. In contrast to 001 oriented domain engineered rhombohedral crystals, tetragonal PIN–PMN–PT crystals exhibited broader temperature usage range and higher thermal/electric field stability, with improved coercive field and mechanical quality factor. © 2010 American Institute of Physics. doi:10.1063/1.3331407
TL;DR: In this article, a doped K4CuNb8O23 solid solution was synthesized and its shear mode dielectric and piezoelectric properties were characterized as a function of temperature.
Abstract: (K0.45Na0.55)NbO3–0.5 mol% K4CuNb8O23 [KNN–KCN] solid solution was synthesized and its shear mode dielectric and piezoelectric properties were characterized as a function of temperature. The doped KNN material was found to possess comparable electric resistivity, piezoelectric, and electromechanical properties with pure KNN, but with a much higher mechanical Qm value, being on the order of 1500. The dielectric permittivity K11T and piezoelectric coefficients d15 for KNN–KCN were found to increase with the increasing temperature, while the electromechanical coupling factors k15 maintain a similar value till the phase transition temperature (To−t∼200°C), above which, the properties drop significantly due to depolarization. The good temperature-dependent properties, together with its high mechanical Qm, demonstrate a practical potential of KNN–KCN materials for high power shear-mode applications.
TL;DR: In this paper, 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.
TL;DR: In this article, the piezoelectric properties of yttrium calcium oxyborate (YCa4O(BO3)3) were studied as a function of orientation and temperature.
Abstract: The piezoelectric single crystal yttrium calcium oxyborate, YCa4O(BO3)3, was studied as a function of orientation and temperature. The resistivity of Y-cut samples was found to be 2.7 × 107 Ω cm at 950 °C, three orders of magnitude higher than langatate crystals. The electromechanical coupling k26 and piezoelectric d26 were found to be 22% and 10 pC/N at room temperature for (ZXw)-30°-cut samples, respectively, maintaining similar values at elevated temperature of 950 °C, exhibiting temperature independent behavior. Furthermore, the highest temperature frequency coefficient was obtained in (ZXw)-33°-cut samples, being –91 ppm/K. The temperature independent piezoelectric properties, together with the high resistivity and mechanical quality factor Q (∼2000 at 950 °C), suggest the YCOB crystal to be a good candidate for high temperature sensing applications. (© 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)
TL;DR: The temperature dependence of the shear piezoelectric responses in relaxor-PbTiO(3) based perovskite crystals with rhombohedral, orthorhombic, and tetragonal phases were investigated and high shear pieselectric coefficients (d(24)) and good thermal stability were predicted in orthorHombic crystals, owing to the "vertical" orthor hombic-rhombohedral phase boundary.
Abstract: The temperature dependence of the shear piezoelectric responses in relaxor-PbTiO3 based perovskite crystals with rhombohedral, orthorhombic, and tetragonal phases were investigated. Based on thermodynamic analysis, high shear piezoelectric coefficients (d24) and good thermal stability were predicted in orthorhombic crystals, owing to the “vertical” orthorhombic-rhombohedral phase boundary. By resonance measurements, shear piezoelectric coefficient d24 was found to be on the order of ∼2100 pC/N at room temperature, maintaining same value over the temperature range of −50–100 °C. In contrast, the shear piezoelectric coefficients d15, with values of 3300, 3600, and 2000 pC/N at room temperature for rhombohedral, orthorhombic, and tetragonal crystals, respectively, exhibited strong temperature dependent behavior due to their respective ferroelectric-ferroelectric phase transitions.
TL;DR: In this article, the authors evaluated the properties of PMNT single crystals with various modifications to see if self-heating may be reduced by decreasing the mechanical and electrical losses within the active material.
Abstract: The use of single crystals based on the solid solution (1−x)Pb(Mg1/3Nb2/3)O3−xPbTiO3 (PMNT) has been demonstrated in many piezoelectric devices, but the low mechanical quality factor has limited its use in high power projector applications. In this work, 33-mode properties of PMNT single crystals with various modifications were evaluated to see if self-heating may be reduced by decreasing the mechanical and electrical losses within the active material. Three modifications were evaluated: incorporating ternary components, adding acceptor dopants, or orienting the crystal along different crystallographic directions. The electromechanical properties of these modified crystals were evaluated under increasing levels of dynamic strain. The results suggest that modified single crystal PMNT may improve the source level from a projector while reducing thermal effects from self-heating, making them appropriate for high power applications.
TL;DR: Temperature dependent dielectric behavior of the crystals suggested that the observed thickness dependence in PMN-PT was strongly related to their relatively large domain size, as evidenced by the broadened [002] peaks in the x-ray diffraction pattern.
Abstract: The dielectric and piezoelectric properties of Pb(Mg(13)Nb(23))O(3)-PbTiO(3) (PMN-PT) and Pb(In(12)Nb(12))O(3)-Pb(Mg(13)Nb(23))O(3)-PbTiO(3) (PIN-PMN-PT) ferroelectric single crystals were investigated as a function of thicknessscale in monolithic and piezoelectricpolymer 1-3 composites. For the case of PMN-PT single crystals, the dielectric (epsilon33Tepsilon0) and electromechanical properties (k(33)) were found to significantly decrease with decreasing thickness (500-40 mum), while minimal thickness dependency was observed for PIN-PMN-PT single crystals. Temperature dependent dielectric behavior of the crystals suggested that the observed thickness dependence in PMN-PT was strongly related to their relatively large domain size (>10-20 mum). As anticipated, 1-3 composite comprised of PIN-PMN-PT crystals exhibited superior properties to that of PMN-PT composite at high frequencies (>20 MHz). However, the observed couplings, being on the order of 80%, were disappointedly low when compared to their monolithic counterparts, the result of surface damage introduced during the dicing process, as evidenced by the broadened [002] peaks in the x-ray diffraction pattern.
TL;DR: In this article, the piezoelectric properties of Pb(In0.5Nb 0.5)O3-Pb(Mg1/3Nb2/3)-PbTiO3 crystals with various engineered domain configurations were investigated.
Abstract: The piezoelectric properties of Pb(In0.5Nb0.5)O3–Pb(Mg1/3Nb2/3)O3–PbTiO3 crystals with various engineered domain configurations were investigated. Rhombohedral and monoclinic/orthorhombic crystals poled along their crystallographic [011] directions were found to possess macroscopic mm2 symmetry, with “2R” and “1O” domain, respectively. Crystals with the “2R” domain configuration were found to exhibit high extensional piezoelectric coefficients d33 (∼1300 pC/N) and d32 (∼−1680 pC/N), while crystals with the “1O” configuration possessed high shear coefficients d15 (∼3500 pC/N) and d24 (∼2070 pC/N), with relatively low extensional piezoelectric coefficients d33 (∼340 pC/N) and d32 (∼−260 pC/N). The observed results were explained by “polarization rotation” model, as related to their respective domain configurations.
TL;DR: In this article, the electrical properties of the fresnoite BaO-TiO2-SiO2 system were studied over a range of amorphous and crystalline microstructures using as-quenched glass (BTS-gl), partially crystallized glass (bTS-pc, heat treated at 740°C for 100 min) and fully crystallized Glass Ceramic (bts-gc, heat treating at 750°Cfor 180 min).
Abstract: The electrical properties of the fresnoite BaO–TiO2–SiO2 system were studied over a range of amorphous and crystalline microstructures using as-quenched glass (BTS-gl), partially crystallized glass (BTS-pc, heat treated at 740°C for 100 min) and fully crystallized glass ceramic (BTS-gc, heat treated at 750°C for 180 min). Combination of impedance and moduli plots along with equivalent circuit models were utilized in an attempt to understand the contributions arising from different regions in the glass ceramic, i.e. the glassy matrix, crystalline phase, and crystal–glass interface region. Electrical conductivity of the samples exhibited frequency dispersions at different temperatures suggesting localized motion of ions. The activation energies calculated from dc resistivity–temperature plots (Edc) and relaxation frequency–temperature plots (Ef) seem to increase as the degree of crystallinity increases suggesting that ionic transport becomes more difficult in crystallized glasses.
TL;DR: In this article, the effect of (Li,Ce) substitution for A-site on the properties of (Na 0.52 K 0.42 Li 0.06 )O 9-based ceramics was investigated.
Abstract: The effect of (Li,Ce) substitution for A-site on the properties of [(Na 0.52 K 0.42 Li 0.06 )Bi] 0.5 Bi 2 (Nb 1.88 Sb 0.06 Ta 0.06 )O 9 -based ceramics was investigated. The piezoelectric activity of [(Na 0.52 K 0.42 Li 0.06 )Bi] 0.5 Bi 2 (Nb 1.88 Sb 0.06 Ta 0.06 )O 9 -based ceramics is significantly improved by the modification of lithium and cerium. The Curie temperature (T C ) gradually decreases from 625 to 605 °C with increasing the (Li,Ce) modification. The piezoelectric coefficient d 33 of the [(Na 0.52 K 0.42 Li 0.06 )Bi] 0.44 (Li,-Ce) 0.03 [] 0.03 Bi 2 (Nb 1.88 Sb 0.06 Ta 0.06 )O 9 ceramic was found to be 28 pC/N, the highest value among the [(Na 0.52 K 0.42 Li 0.06 )-Bi] 0.5 Bi 2 (Nb 1.88 Sb 0.06 Ta 0.06 )O 9 -based ceramics, also almost 50% higher than the reported d 33 values of other Bismuth layer-structured ferroelectric (BLSF) systems (~5-19 pC/N). The planar coupling factor k p and k t were found to be 7.0 and 28.0%, together with the high T C (~610 °C) and stable piezoelectric properties, demonstrating that the (Li,Ce) modified [(Na 0.52 K 0.42 Li 0.06 )Bi] 0.5 Bi 2 (Nb 1.88 Sb 0.06 Ta 0.06 )O 9 -based material a promising candidate for high temperature applications.
TL;DR: In this article, 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.
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)
01 Oct 2010
TL;DR: In this paper, the effect of acceptor dopant, Mn, on mechanical loss and other electromechanical properties was studied in comparison with pure PIN-PMN-PT single crystal under high and low electric fields.
Abstract: Mn doped PIN-PMN-PT single crystals with diameter of 50mm have been successfully grown by the Bridgman method along , and orientations. The effect of the acceptor dopant, Mn, on mechanical loss and other electromechanical properties was studied in comparison with pure PIN-PMN-PT single crystal under high and low electric fields. A complete set of piezoelectric, dielectric and elastic properties was derived from resonance measurements. It was demonstrated that by doping Mn, Q M increases 4–5 times to 700–1000 in -poled longitudinal samples without any compromise in electromechanical coupling (k 33 ). Mn doped PIN-PMN-PT crystals also show strong anisotropy. For -poled longitudinal samples, Q M and E C increase to above 1000 and 8–10kV/cm, respectively, which is comparable to “hard” PZT ceramics. The fatigue behavior was investigated as function of crystal orientation and magnitude of the electric field. Polarization degradation was observed to suddenly occur along orientation above 100 cycles of 15kV/cm bipolar field, while nearly no fatigue was seen along orientation.
Patent•
16 Mar 2010TL;DR: In this article, a domain engineered relaxor-PT single crystals having a dielectric loss of about 0.2, a high electromechanical coupling factor greater than about 85, and high mechanical quality factor higher than about 500 is disclosed.
Abstract: A domain engineered relaxor-PT single crystals having a dielectric loss of about 0.2%, a high electromechanical coupling factor greater than about 85%, and high mechanical quality factor greater than about 500 is disclosed. In one embodiment, the relaxor-PT material has the general formula, Pb(B 1 B 2 )O 3 —Pb(B 3 )O 3 , where B 1 may be one ion or combination of Mg 2+ , Zn 2+ , Ni 2+ , Sc 3+ , In 3+ , Yb 3+ , B 2 may be one ion or combination of Nb 5+ , Ta 5+ , W 6+ , and B 3 may be Ti 4+ or combination of Ti 4+ with Zr 4+ and/or Hf 4+ .
TL;DR: In this article, the reference frame corresponds to a reference frame rotated around the z-axis by 180° as described in Ref. 2, and the authors provide a revised Table 22 for the complete data set based on the standard coordinate system.
Abstract: In our publication1 the reference frame corresponds to a reference frame rotated around the z-axis by 180° as described in Ref. 2. To avoid confusion, we provide a revised Table Table22 for the complete data set based on the standard coordinate system (the 0° rotation one in Ref. 2).
Table 2
(In standard coordinates) Measured and derived material properties of 0.26Pb(In1∕2Nb1∕2)O3–0.46Pb(Mg1∕3Nb2∕3)O3–0.28PbTiO3 single-domain single crystal poled in [111]c (density: ρ=8102 kg∕m ...
Figures Figures22233 were recalculated based on the standard coordinate system. The maximum values of d33∗, k33∗, e33∗, and s33∗ occur at 60.7°, 57.8°, 90°, and 51.5°, respectively, from the poling direction [111]c.
Figure 2
Orientation dependence of piezoelectric constant d33∗ (a) and elastic compliance s33∗ (b), of single domain 0.26Pb(In1∕2Nb1∕2)O3–0.46Pb(Mg1∕3Nb2∕3)O3–0.28PbTiO3 single crystal.
Figure 3
Orientation dependence of dielectric constant e33∗ (a) and electromechanical coupling factor k33∗ (b) of single domain 0.26Pb(In1∕2Nb1∕2)O3–0.46Pb(Mg1∕3Nb2∕3)O3–0.28PbTiO3 single ...
TL;DR: In this article, the feasibility of producing piezoelectric drill/corers for a temperature up to 500 deg C was investigated. And the results of the feasibility study were presented and the future works for performance improvements were discussed.
Abstract: Venus is one of the many significant scientific targets for NASA. New rock sampling tools with the ability to be operated at high temperatures of the order of 460 deg C are required for surface in-situ sampling/analysis missions. Piezoelectric materials such as LiNbO? crystals and Bismuth Titanate are potentially operational at the temperature range found on the surface of Venus. A study of the feasibility of producing piezoelectric drills for a temperature up to 500 deg C was conducted. The study includes investigation of the high temperature properties of piezoelectric crystals and ceramics with different formulas and doping. Several prototypes of Ultrasonic/Sonic Drill/Corers (USDC) driven by transducers using the high temperate piezoelectric ceramics and single LiNbO? crystal were fabricated. The transducers were analyzed by scanning the impedance at room temperature and 500 deg C under both low and high voltages. The drilling performances were tested at temperature up to 500 deg C. Preliminary results were previously reported [Bao et al, 2009]. In this paper, the progress is presented and the future works for performance improvements are discussed.
TL;DR: In this article, a morphotropic phase boundary (MPB) composition of PYNT was studied as a function of temperature and the dielectric and piezoelectric properties were characterized for high temperature shear sensor and inkjet actuator applications.
11 Mar 2010
Journal Article•
TL;DR: In this paper, the effect of K content on the properties of LiCe co-substituted (Na 1−x K x ) 0.5 Bi 4 O 15 -based ceramics was investigated.
Abstract: The effect of K content on the properties of LiCe co-substituted (Na 1―x K x ) 0.5 Bi 4.5 Ti 4 O 15 -based ceramics was investigated. The Curie temperature (T C ) gradually decreases from 641 to 551 °C with increasing the K content. The piezoelectric coefficient d 33 , thickness coupling factor k t , and mechanical quality factor Q of (Na 0.5 Bi 0.5 ) 0.80 (Li 0.5 Ce 0.5 ) 0.10 [] 0.10 Bi 4 Ti 4 O 15 (x = 0.00) ceramic were found to be 28 pC/N, 25%, and 2693, respectively, together with the high T C (∼641 °C) and stable piezoelectric properties, demonstrating that the (LiCe) modified Na 0.5 Bi 4.5 Ti 4 O 15 -based material a promising candidate for high temperature applications.