About this Journal Submit a Manuscript Table of Contents
Smart Materials Research
Volume 2011 (2011), Article ID 452901, 6 pages
http://dx.doi.org/10.1155/2011/452901
Review Article

Pb(Mg1/3Nb2/3)O3–PbTiO3 (PMN-PT) Material for Actuator Applications

1Electronic Ceramics Department, Jožef Stefan Institute, Jamova 39, 1000 Ljubljana, Slovenia
2HIPOT-RR, Šentpeter 18, 8222 Otočec, Slovenia

Received 1 December 2010; Accepted 24 January 2011

Academic Editor: C. R. Bowen

Copyright © 2011 Hana Uršič et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

Due to its large piezoelectric and electrostrictive responses to an applied electric field the ()Pb(Mg1/3Nb2/3)O3PbTiO3 (PMN-PT) solid solution has been widely investigated as a promising material for different actuator applications. This paper discusses some of the recent achievements in the field of PMN-PT piezoelectric and electrostrictive actuators manufactured from PMN-PT single crystals, bulk ceramics, or thick films. The functional properties of PMN-PT materials and some representative examples of the investigated PMN-PT actuator structures and their applications are reported.

1. Introduction

In recent years, the fabrication of ferroelectric materials has been extensively studied, with a particular emphasis on micro- and nanodevices. Ferroelectric and piezoelectric films are mostly based on lead oxide compounds, mainly Pb(Zr,Ti)O3 (PZT) solid solutions. An alternative to PZT are the relaxor-based systems, that is, the Pb(Mg1/3Nb2/3)O3-PbTiO3 (in short form PMN-PT) material. PMN-PT-based materials are characterized by a high dielectric permittivity, high piezoelectric properties, high electrostriction, and are suitable for applications in multilayer capacitors, actuators, sensors, and electro-optical devices [1, 2].

Piezoelectric and electrostrictive actuators can be used in a wide range of applications, such as micropositioners, to precisely control the positioning in low- to very-heavy-load applications, miniature ultrasonic motors, and adaptive mechanical dampers [35]. In mechanical systems, these actuators can generate forces or pressures under static or high-frequency conditions and so activate a suitable mechanical device [6]. Bimorph, bending-type actuators are employed for applications that require a large displacement output, that is, fluid control devices [4, 7], robotic systems [4], and swing CCD (charge-coupled device) mechanisms [7, 8]. In an optical system, an actuator can be used to move a mirror or another optical switch [9, 10], and so forth. Depending on the application, specific constructions of the piezoelectric and electrostrictive actuators are designed, mainly with the appropriate bulk piezoceramic elements. However, recently, there has been a growing interest in micro- and nanometre-sized piezoelectric and electrostrictive actuators, which are particularly attractive for advanced applications in novel research fields, such as micromechanics, robotics, and microfluidics. The active piezoelectric elements integrated into microelectromechanical systems (MEMS) or nanoelectromechanical systems (NEMS) should be a few tens of μm or nm thick, respectively. For that reason, thick- and thin-film piezoelectric actuators are considered as a promising solution for future electromechanical systems and smart-structure technologies. In this paper, the results of investigations of PMN-PT material and possible actuator applications are reviewed. In the first section, the functional properties of the PMN-PT material (single crystals, ceramics, as well as films) are discussed, and in the second section, some examples of PMN-PT actuators are summarized.

2. Functional Properties of the PMN-PT Material System

The morphotropic phase boundary (MPB) in the PMN-PT system is located close to the composition. These MPB compositions of the PMN-PT material remain the subject of intense research, while the functional properties of the material depend on the phase composition. It is worth mentioning that the strong piezoelectric properties of PMN-PT solid solutions are related to the “polarization rotation” between the adjacent rhombohedral and tetragonal phases through one (or more) intermediate phase(s) of low symmetry, that is, a monoclinic (orthorhombic or triclinic) phase [11, 12]. As a consequence, the observation of a low-symmetry phase, typically a monoclinic one, may suggest strong electromechanical responses.

The PMN-PT ceramics and a single crystal of the composition on the MPB can have piezoelectric coefficients d33 as high as 700 pC/N [13, 14] and 1500–2800 pC/N [1, 15, 16], respectively. The commonly used poling electric fields for the PMN-PT material vary from 2 to 3.5 kV/mm [13, 14, 1722]. On the other hand, the PMN-PT material with compositions shows relaxor behaviour [2325] and are known as good electrostrictive materials [2629]. Likewise, the electrostrictive effect of the MPB compositions was also reported to be relatively high [30, 31]. Due to the large responses of the PMN-PT material to the applied electric field, this material is suitable for actuators. The response of the bending structure with PMN-PT layers to the electric field can be written as where is the strain, (V/m) is the electric field, (m/V) is the piezoelectric coefficient, and (m2/V2) is the electrostrictive coefficient. Therefore, the characteristics of the actuators made by using PMN-PT differ from those of the linear piezoelectric actuators (e.g., PZT actuators), mainly because of the high electrostrictive effect in the PMN-PT material. This effect takes place particularly at larger electric fields. However, under low applied el. fields, that is, lower than 1.5 kV/cm for the MPB compositions [32, 33], the major effect is the piezoelectric effect. Hence, at low el. fields, not just PZT, but also PMN-PT actuators show a linear response to the applied el. field. For some applications, the 1.5 kV/cm is a large input value, for example, in mobile devices where a voltage of only 10 V is normally used [34]. In any case, the PMN-PT material can be appropriate for bending actuators in applications operating at higher voltages, where the linearity of the response to the applied el. field is not required.

The PMN-PT material can be processed as a single crystal, a polycrystalline ceramic, and in thick- or thin-film forms, each of them having different functional properties and, therefore, appropriate for different applications. The best functional properties for actuator applications are obtained for PMN-PT single crystals. So, the possibility of processing such single crystals is an important advantage of the PMN-PT material, in contrast to PZT-based materials that were processed as polycrystalline ceramics or thick and thin films. Just recently, the first example of PZT single crystals was reported by Bokov et al. [35]. The elastic () and piezoelectric () coefficients of single crystals, ceramics, and thick films of the PMN-PT composition near the MPB and of the PZT ceramics are collected in Table 1.

tab1
Table 1: The elastic and piezoelectric properties of 0.67PMN-0.33PT single crystals, 0.655PMN-0.345PT ceramics and 0.65PMN-0.35PT thick films on Al2O3 substrates.

The functional properties of the PMN-PT materials depend not only on the material composition [13, 4043] but also on the processing procedure [18, 19], the crystal orientation [16, 44], the compatibility of the functional material with the electrodes, the poling procedure [20, 45], the grain size [17, 46, 47], and the boundary effects imposed by the material system. In the case of thick films, the clamping of the film to the substrate also influences the effective functional properties of the film [48]. In addition, the properties of the PMN-PT material can be modified by the application of mechanical stresses [49]. In thick PMN-PT films, the properties are influenced by thermal stresses generated in films due to a mismatch of the thermal expansion coefficient of the film and the substrate [50, 51]. On the other hand, a chemical interaction between the film and the substrate may result in a deterioration of the material’s functional properties [52]. In order to prevent such interactions, the use of a Pb(Zr,Ti)O3 barrier layer was proposed [31, 50].

3. PMN-PT Actuators

PMN-PT actuators are manufactured by using single crystals or bulk ceramics; however, PMN-PT thick-film actuators were also investigated. Depending on the application, different constructions and realisations of the actuator structures are possible. The simplest actuator design is a free-standing cantilever beam that can be realized as a unimorph, bimorph, or multimorph structure. In addition to cantilever-type actuators, there are also the bridge- and the membrane-type actuators. In combination with the materials and technologies enabling 3D structuring, even arbitrarily shaped actuator structures can be feasible. Furthermore, actuators made from a composite material, where one of materials is PMN-PT, can also be designed.

3.1. Actuator Structures Processed from PMN-PT Single Crystals

The most common type of PMN-PT actuators reported in the literature is the bending type [34, 37, 53]. Kim et al. [37] showed that the tip displacement of the bending-type PMN-PT single-crystal actuators can be several times larger than ones made from PZT ceramic actuators of the same design. The reported normalized displacement (displacement per unit length of the actuator) for a PMN-PT single-crystal actuator and PZT ceramic actuators were 38 μm/cm and 2.5 μm/cm at 10 V (0.67 kV/cm), respectively. Another benefit of the PMN-PT single-crystal bending actuators is that they operate at relatively low voltages and, therefore, with a low power consumption. Ko et al. [34] reported the use of an actuator structure composed of two parallel multilayer PMN-PT actuators for optical-disk-drive applications [34, 54].

Stacked structures with active PMN-PT single-crystal layers were also considered as a solution for an improvement of the bending capabilities of actuators. Woody et al. [55] discussed the results of an investigation of the PMN-PT actuators for adaptive structures in space applications. The actuators were realised as stacked structures with several (up to 40) 0.5-mm-thick active 0.68PMN-0.32PT single-crystal layers with a diameter of 5 mm. It was demonstrated that the actuators had at least two-times-lower power requirements, more than three-times-higher strains generated, higher displacements at cryogenic temperatures, and high bandwidth in comparison to the PZT actuators.

Park and Horsley [58] reported on the fabrication and characterisation of an MEMS-based deformable mirror for ophthalmologic adaptive optics constructed by using single-crystal PMN-PT. Basically, the structure is composed of a 30 μm active PMN-PT membrane layer bonded onto a 5 μm passive single-crystal silicon layer with a 1-μm-thick conductive epoxy. The maximum displacement of such a membrane structure (with 100-nm Cr/Au electrodes on the top and bottom) was over 20 μm for the applied voltage 20 Vpp, which was found to be appropriate for the application.

Wilkie et al. [59] reported on the results of their investigation of a composite actuator structure manufactured by using a layer of 0.68PMN-0.32PT single-crystal fibres in an epoxy matrix, packaged between interdigitated electrode polyimide films.

3.2. Actuator Structures Processed from the PMN-PT Bulk Ceramics and Films

Ngernchuklin et al. [60] processed piezoelectric/electrostrictive PMN-PT ceramic actuators by dry pressing the powder and sintering at 1150°C. The actuators were prepared as a bilayer composite of 0.65PMN-0.35PT and 0.90PMN-0.10PT layers. In an earlier report [56] from the same research group, there are the results of an investigation of piezoelectric/electrostrictive PMN-PT actuators with dimensions of 2.6 cm × 11 mm × 2.3 mm prepared by tape casting. The maximum tip displacement of those actuators was 11 μm at 3 kV/cm (a normalized tip displacement per length of 4 μm/cm). Recently, the same authors [4] reported on improved actuator characteristics; that is, the tip displacement of a piezoelectric/electrostrictive PMN-PT actuator with dimensions of 3 cm × 8 mm × 1.2 mm was up to 40 μm at 5 kV/cm (the calculated normalized displacement is 13 μm/cm).

There are only few reports on thick-films actuators. Generally, thick-film piezoelectric actuators have smaller displacements and exert weaker forces in comparison to their bulk relatives. This is because a stiff and relatively thick substrate in comparison to the active piezoceramic film always reduces the bending ability of the thick-film actuator structure. However, a novel approach to manufacturing large-displacement 0.65PMN-0.35PT/Pt (PMN-PT/Pt) actuators by using thick-film technology based on screen printing of the functional layers was recently presented by Uršič et al. in [32]. The actuators were prepared by screen printing the PMN-PT film over the Pt electrode directly onto an Al2O3 substrate, which results in a poor adhesion between the electrode and the substrate, enabling the PMN-PT/Pt thick-film composite structure to be simply separated from the substrate. In this way, a “substrate-free” actuator structure was manufactured. The normalized displacement of these actuators is very high, that is, 55 μm/cm at 3.6 kV/cm [32]. In Figure 1, the scheme of the cross-section of the PMN-PT/Pt actuators and photographs of the actuators are shown.

fig1
Figure 1: (a) The scheme of the cross-section of the PMN-PT/Pt actuator. (b) The actuator with dimensions 1.8 cm × 2.5 mm × 60 μm (50-μm-thick PMN-PT film and 10-μm-thick Pt electrode) after processing (left) and during the measurement of the displacement (right).

4. Discussion and Summary

The PMN-PT ceramics and the single crystal with a composition on the MPB have the piezoelectric coefficients d33 as high as 700 pC/N and 1500–2800 pC/N, respectively. On the other hand, the PMN-PT materials with the compositions show relaxor behaviour and are the electrostrictive materials. Due to the large responses of the PMN-PT material to the applied electric field, this material is suitable for actuators, especially for the bending-type actuators.

One important advantage of the PMN-PT material is that it can be processed as a single crystal, a polycrystalline ceramic, and thick- or thin-film forms, each of them having different functional properties and therefore appropriate for different applications. However, the best functional properties were obtained for actuator structures made by using PMN-PT single crystals. On the other hand, the disadvantage of PMN-PT material is that it can be depoled by the application of negative electric field due to switch of the domain walls.

In order to compare the performances of the PMN-PT bending-type actuators prepared from single crystals, ceramics, and thick films, the normalized tip displacements versus the applied electric fields are summarized in Table 2. For comparison, PZT actuators are also added. The largest bending of the actuators was obtained for PMN-PT actuators processed from a single crystal. However, the actuators prepared from PMN-PT thick films also show an extremely large displacement. In comparison to the PMN-PT and PZT actuators prepared from bulk ceramics or thick films, these actuators show a 5-times larger displacement.

tab2
Table 2: The normalized displacement of PMN-PT and PZT bending-types actuators.

PMN-PT actuators have many potential applications. Depending on the application, different constructions and realisations of the actuator structures are possible. Structures including piezo-active PMN-PT single-crystal layers were reported, for example, an MEMS-based deformable mirror for ophthalmologic adaptive optics and much larger stacked actuators for adaptive structures in space applications. The state of the art in the processing of PMN-PT actuators is the development of new, effective functional structures with the desired output for specific applications. There are still a number of challenges to be faced in the production of PMN-PT actuators and wide possibilities for further improvements in their performance to meet the industrial demands for production.

Acknowledgment

The financial support of the Slovenian Research Agency in the frame of the Program Electronic Ceramics, Nano-, 2D, and 3D Structures (P2-0105) is gratefully acknowledged.

References

  1. S. E. Park and T. R. Shrout, “Ultrahigh strain and piezoelectric behavior in relaxor based ferroelectric single crystals,” Journal of Applied Physics, vol. 82, no. 4, pp. 1804–1811, 1997. View at Scopus
  2. S. E. Park and T. R. Shrout, “Relaxor based ferroelectric single crystals for electro-mechanical actuators,” Materials Research Innovations, vol. 1, no. 1, pp. 20–25, 1997.
  3. M. Allahverdi, A. Hall, R. Brennan, M. E. Ebrahimi, N. Marandian Hagh, and A. Safari, “An overview of rapidly prototyped piezoelectric actuators and grain-oriented ceramics,” Journal of Electroceramics, vol. 8, no. 2, pp. 129–137, 2002. View at Publisher · View at Google Scholar · View at Scopus
  4. A. Hall, E. K. Akdogan, and A. Safari, “Fatigue properties of piezoelectric-electrostrictive Pb(Mg1/3, Nb2/3)O3–PbTiO3 monolithic bilayer composites,” Journal of Applied Physics, vol. 100, no. 9, Article ID 094105, 2006. View at Publisher · View at Google Scholar · View at Scopus
  5. H. Takagi, K. Sakata, and T. Takenaka, “Electrostrictive properties of Pb(Mg1/3Nb2/3)O3-based relaxor ferroelectric ceramics,” Japanese Journal of Applied Physics Part 1, vol. 32, no. 9, pp. 4280–4283, 1993. View at Scopus
  6. D. J. Arbogast and F. T. Calkins, “Electrical system for electrostrictive bimorph actuator,” US patent no. 6,888,291 B2.
  7. H. Ikawa and M. Takemoto, “Products and microwave dielectric properties of ceramics with nominal compositions (Ba1xCax)(B1/2B1/2')O3  (B=Y3+,Nd3+,Gd3+;B'=Nb5+,Ta5+),” Materials Chemistry and Physics, vol. 79, no. 2-3, pp. 222–225, 2003. View at Publisher · View at Google Scholar · View at Scopus
  8. C. Tanuma, “A parallel-bimorph-type piezoelectric actuator for high-resolution imager,” Japanese Journal of Applied Physics Part 1, vol. 38, no. 9, pp. 5603–5607, 1999. View at Scopus
  9. G. Rodrigues, R. Bastaits, S. Roose, et al., “Modular bimorph mirrors for adaptive optics,” Optical Engineering, vol. 48, no. 3, Article ID 034001, 2009.
  10. E. H. Yang, K. Shcheglov, and S. Trolier-McKinstry, “Concept, modeling and fabrication techniques for large-stroke piezoelectric unimorph deformable mirrors,” in MOEMS and Miniaturized Systems III, Proceeding of SPIE, pp. 326–333, January 2003. View at Scopus
  11. B. Noheda, D. E. Cox, G. Shirane, S. E. Park, L. E. Cross, and Z. Zhong, “Polarization rotation via a monoclinic phase in the piezoelectric 92% PbZn1/3Nb2/3O3-8%PbTiO,” Physical Review Letters, vol. 86, no. 17, pp. 3891–3894, 2001. View at Publisher · View at Google Scholar · View at Scopus
  12. M. Davis, D. Damjanovic, and N. Setter, “Electric-field-, temperature-, and stress-induced phase transitions in relaxor ferroelectric single crystals,” Physical Review B, vol. 73, no. 1, Article ID 014115, 16 pages, 2006. View at Publisher · View at Google Scholar · View at Scopus
  13. J. Kelly, M. Leonard, C. Tantigate, and A. Safari, “Effect of composition on the electromechanical properties of (1-x)Pb(Mg1/3Nb2/3)O3XPbTiO3 ceramics,” Journal of the American Ceramic Society, vol. 80, no. 4, pp. 957–964, 1997. View at Scopus
  14. Z. Xia, L. Wang, W. Yan, Q. Li, and Y. Zhang, “Comparative investigation of structure and dielectric properties of Pb(Mg1/3Nb2/3)O3–PbTiO3 (65/35) and 10% PbZrO3-doped Pb(Mg1/3Nb2/3)O3–PbTiO3 (65/35) ceramics prepared by a modified precursor method,” Materials Research Bulletin, vol. 42, no. 9, pp. 1715–1722, 2007. View at Publisher · View at Google Scholar · View at Scopus
  15. T. R. Shrout, Z. P. Chang, N. Kim, and S. Markgraf, “Dielectric behavior of single crystals near the (1-X) Pb(Mg1/3Nb2/3)O3-(x) PbTiO3 morphotropic phase boundary,” Ferroelectrics Letters, vol. 12, no. 3, pp. 63–69, 1990.
  16. R. Zhang, B. Jiang, and W. Cao, “Elastic, piezoelectric, and dielectric properties of multidomain 0.67Pb(Mg1/3Nb2/3)O3–0.33PbTiO3 single crystals,” Journal of Applied Physics, vol. 90, no. 7, pp. 3471–3475, 2001. View at Publisher · View at Google Scholar · View at Scopus
  17. M. Algueró, J. Ricote, R. Jiménez et al., “Size effect in morphotropic phase boundary Pb (Mg1/3Nb2/3)O3–PbTiO3,” Applied Physics Letters, vol. 91, no. 11, Article ID 112905, 2007. View at Publisher · View at Google Scholar · View at Scopus
  18. M. Algueró, A. Moure, L. Pardo, J. Holc, and M. Kosec, “Processing by mechanosynthesis and properties of piezoelectric Pb(Mg1/3Nb2/3)O3–PbTiO3 with different compositions,” Acta Materialia, vol. 54, no. 2, pp. 501–511, 2006. View at Publisher · View at Google Scholar · View at Scopus
  19. E. R. Leite, A. M. Scotch, A. Khan et al., “Chemical heterogeneity in PMN-35PT ceramics and effects on dielectric and piezoelectric properties,” Journal of the American Ceramic Society, vol. 85, no. 12, pp. 3018–3024, 2002. View at Scopus
  20. H. Uršič, J. Tellier, M. Hrovat, et al., “The effect of poling on the properties of 0.65Pb(Mg1/3Nb2/3)O3–0.35PbTiO3 ceramics,” Japanese Journal of Applied Physics, vol. 50, no. 3, 2011. In press.
  21. S. Gentil, D. Damjanovic, and N. Setter, “Pb(Mg1/3Nb2/3)O3 and (1x)Pb((Mg1/3Nb2/3)O3xPbTiO3 relaxor ferroelectric thick films: processing and electrical characterization,” Journal of Electroceramics, vol. 12, no. 3, pp. 151–161, 2004. View at Publisher · View at Google Scholar · View at Scopus
  22. D. Kuščer, M. Skalar, J. Holc, and M. Kosec, “Processing and properties of 0.65Pb(Mg1/3Nb2/3)O3–0.35PbTiO3 thick films,” Journal of the European Ceramic Society, vol. 29, no. 1, pp. 105–113, 2009. View at Publisher · View at Google Scholar · View at Scopus
  23. L. E. Cross, “Relaxor ferroelectrics,” Ferroelectrics, vol. 76, no. 1, pp. 241–267, 1987.
  24. S. L. Swartz, T. R. Shrout, W. A. Schulze, and L. E. Cross, “Dielectric properties of lead-magnesium niobate ceramics,” Journal of the American Ceramic Society, vol. 67, no. 5, pp. 311–315, 1984. View at Scopus
  25. S. L. Swartz and T. R. Shrout, “Fabrication of perovskite lead magnesium niobate,” Materials Research Bulletin, vol. 17, no. 10, pp. 1245–1250, 1982. View at Scopus
  26. K. Uchino, S. Nomura, L. E. Cross, S. J. Jang, and R. E. Newnham, “Electrostrictive effect in lead magnesium niobate single crystals,” Journal of Applied Physics, vol. 51, no. 2, pp. 1142–1145, 1980. View at Publisher · View at Google Scholar · View at Scopus
  27. J. Zhao, Q. M. Zhang, N. Kim, and T. Shrout, “Electromechanical properties of relaxor ferroelectric lead magnesium niobate-lead titanate ceramics,” Japanese Journal of Applied Physics, Part 1, vol. 34, no. 10, pp. 5658–5663, 1995. View at Scopus
  28. Z. Kighelman, D. Damjanovic, and N. Setter, “Electromechanical properties and self-polarization in relaxor Pb(Mg1/3Nb2/3)O3 thin films,” Journal of Applied Physics, vol. 89, no. 2, pp. 1393–1401, 2001. View at Publisher · View at Google Scholar · View at Scopus
  29. V. S. Vikhnin, R. Blinc, and R. Pirc, “Mechanisms of electrostriction and giant piezoelectric effect in relaxor ferroelectrics,” Journal of Applied Physics, vol. 93, no. 12, pp. 9947–9952, 2003. View at Publisher · View at Google Scholar · View at Scopus
  30. A. A. Bokov and Z. G. Ye, “Giant electrostriction and stretched exponential electromechanical relaxation in 0.65Pb(Mg1/3Nb2/3)O3–0.35PbTiO3 crystals,” Journal of Applied Physics, vol. 91, no. 10, p. 6656, 2002. View at Publisher · View at Google Scholar · View at Scopus
  31. H. Uršič, M. Škarabot, M. Hrovat et al., “The electrostrictive effect in ferroelectric 0.65Pb(Mg1/3Nb2/3)O3–0.35PbTiO3 thick films,” Journal of Applied Physics, vol. 103, no. 12, Article ID 124101, 2008. View at Publisher · View at Google Scholar · View at Scopus
  32. H. Uršič, M. Hrovat, J. Holc et al., “A large-displacement 65Pb(Mg1/3Nb2/3)O3–35PbTiO3/Pt bimorph actuator prepared by screen printing,” Sensors and Actuators B, vol. 133, no. 2, pp. 699–704, 2008. View at Publisher · View at Google Scholar · View at Scopus
  33. Z. Feng, T. He, H. Xu, H. Luo, and Z. Yin, “High electric-field-induced strain of Pb(Mg1/3Nb2/3)O3–PbTiO3 crystals in multilayer actuators,” Solid State Communications, vol. 130, no. 8, pp. 557–562, 2004. View at Publisher · View at Google Scholar · View at Scopus
  34. B. Ko, J. S. Jung, and S. Y. Lee, “Design of a slim-type optical pick-up actuator using PMN-PT bimorphs,” Smart Materials and Structures, vol. 15, no. 6, pp. 1912–1918, 2006. View at Publisher · View at Google Scholar · View at Scopus
  35. A. A. Bokov, X. Long, and Z.-G. Ye, “Optically isotropic and monoclinic ferroelectric phases in Pb(Zr1xTix)O3 (PZT) single crystals near morphotropic phase boundary,” Physical Review B, vol. 81, no. 17, Article ID 172103, 2010. View at Publisher · View at Google Scholar
  36. M. Algueró, C. Alemany, L. Pardo, and M. Pham-Thi, “Piezoelectric resonances, linear coefficients and losses of morphotropic phase boundary Pb(Mg1/3Nb2/3)O3–PbTiO3 ceramics,” Journal of the American Ceramic Society, vol. 88, no. 10, pp. 2780–2787, 2005. View at Publisher · View at Google Scholar · View at Scopus
  37. K. C. Kim, Y. S. Kim, H. J. Kim, and S. H. Kim, “Finite element analysis of piezoelectric actuator with PMN-PT single crystals for nanopositioning,” Current Applied Physics, vol. 6, no. 6, pp. 1064–1067, 2006. View at Publisher · View at Google Scholar · View at Scopus
  38. M. Kosec, J. Holc, D. Kuscer, and S. Drnovšek, “Pb(Mg1/3Nb2/3)O3–PbTiO3 thick films from mechanochemically synthesized powder,” Journal of the European Ceramic Society, vol. 27, no. 13–15, pp. 3775–3778, 2007. View at Publisher · View at Google Scholar · View at Scopus
  39. M. Kosec, H. Uršič, J. Holc, M. Hrovat, D. Kuščer, and B. Malič, “High-performance PMN-PT thick films,” IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control, vol. 57, no. 10, pp. 2205–2212, 2010. View at Publisher · View at Google Scholar · View at PubMed
  40. Z. Feng, X. Zhao, and H. Luo, “Electric field effects on the domain structures and the phase transitions of 0.62Pb(Mg1/3Nb2/3)O3–0.38PbTiO3 single crystals with different orientations,” Journal of Physics: Condensed Matter, vol. 16, no. 21, pp. 3769–3778, 2004. View at Publisher · View at Google Scholar · View at Scopus
  41. T. Y. Koo and S. W. Cheong, “Dielectric and piezoelectric enhancement due to 90° domain rotation in the tetragonal phase of Pb(Mg1/3Nb2/3)O3–PbTiO3,” Applied Physics Letters, vol. 80, no. 22, p. 4205, 2002. View at Publisher · View at Google Scholar · View at Scopus
  42. A. Sehirlioglu, D. A. Payne, and P. Han, “Effect of poling on dielectric anomalies at phase transitions for lead magnesium niobate-lead titanate crystals in the morphotropic phase boundary region,” Journal of Applied Physics, vol. 99, no. 6, Article ID 064101, 2006. View at Publisher · View at Google Scholar · View at Scopus
  43. A. K. Singh and D. Pandey, “Evidence for MB and MC phases in the morphotropic phase boundary region of (1x)[Pb(Mg1/3Nb2/3)O3]–xPbTiO3: a rietveld study,” Physical Review B, vol. 67, no. 6, Article ID 064102, 2003. View at Publisher · View at Google Scholar
  44. R. Zhang, B. Jiang, and W. Cao, “Orientation dependence of piezoelectric properties of single domain 0.67Pb1x)[Pb(Mg1/3Nb2/3)O3–0.33PbTiO3 crystals,” Applied Physics Letters, vol. 82, no. 21, pp. 3737–3739, 2003. View at Publisher · View at Google Scholar · View at Scopus
  45. Y. Guo, H. Luo, K. Chen, H. Xu, X. Zhang, and Z. Yin, “Effect of composition and poling field on the properties and ferroelectric phase-stability of Pb1x)[Pb(Mg1/3Nb2/3)O3–PbTiO3 crystals,” Journal of Applied Physics, vol. 92, no. 10, pp. 6134–6138, 2002. View at Publisher · View at Google Scholar · View at Scopus
  46. J. Carreaud, P. Gemeiner, J. M. Kiat et al., “Size-driven relaxation and polar states in PbMg1/3Nb2/3O3-based system,” Physical Review B, vol. 72, no. 17, pp. 1–6, 2005. View at Publisher · View at Google Scholar · View at Scopus
  47. M. Algueró, B. Jiménez, and L. Pardo, “Transition between the relaxor and ferroelectric states for (1x)Pb(Mg1/3Nb2/3)O3xPbTiO3 with x=0.2 and 0.3 polycrystalline aggregates,” Applied Physics Letters, vol. 87, no. 8, Article ID 082910, 3 pages, 2005. View at Publisher · View at Google Scholar · View at Scopus
  48. K. Lefki and G. J. M. Dormans, “Measurement of piezoelectric coefficients of ferroelectric thin films,” Journal of Applied Physics, vol. 76, no. 3, pp. 1764–1767, 1994. View at Publisher · View at Google Scholar
  49. Q. Wan, C. Chen, and Y. P. Shen, “Effects of stress and electric field on the electromechanical properties of Pb1x)[Pb(Mg1/3Nb2/3)O3–0.32PbTiO3 single crystals,” Journal of Applied Physics, vol. 98, no. 2, Article ID 024103, 5 pages, 2005. View at Publisher · View at Google Scholar
  50. H. Uršič, M. Hrovat, J. Holc et al., “Influence of the substrate on the phase composition and electrical properties of 0.65PMN-0.35PT thick films,” Journal of the European Ceramic Society, vol. 30, no. 10, pp. 2081–2092, 2010. View at Publisher · View at Google Scholar · View at Scopus
  51. H. Uršič, M. S. Zarnik, J. Tellier, M. Hrovat, J. Holc, and M. Kosec, “The influence of thermal stresses on the phase composition of 0.65Pb1x)[Pb(Mg1/3Nb2/3)O3–0.35PbTiO3 thick films,” Journal of Applied Physics, vol. 109, no. 1, Article ID 014101, pp. 1–5, 2011. View at Publisher · View at Google Scholar
  52. H. Uršič, M. Hrovat, D. Belavič et al., “Microstructural and electrical characterisation of PZT thick films on LTCC substrates,” Journal of the European Ceramic Society, vol. 28, no. 9, pp. 1839–1844, 2008. View at Publisher · View at Google Scholar · View at Scopus
  53. L. A. Ivan, M. Rakotondrabe, J. Agnus et al., “Comparative material study between PZT ceramic and newer crystalline PMN-PT and PZN-PT materials for composite bimorph actuators,” Reviews on Advanced Materials Science, vol. 24, no. 1-2, pp. 1–9, 2010.
  54. Y. M. Cheong, J. W. Lee, K. Kim et al., “Pickup for small form factor optical drive with 2.3mm height actuator,” Japanese Journal of Applied Physics Part 1, vol. 44, no. 5, pp. 3356–3359, 2005. View at Publisher · View at Google Scholar · View at Scopus
  55. S. C. Woody, S. T. Smith, X. Jiang, and P. W. Rehrig, “Performance of single-crystal Pb(Mg1/3Nb2/3)-32%PbTiO3 stacked actuators with application to adaptive structures,” Review of Scientific Instruments, vol. 76, no. 7, Article ID 075112, 2005. View at Publisher · View at Google Scholar · View at Scopus
  56. A. Hall, M. Allahverdi, E. K. Akdogan, and A. Safari, “Piezoelectric/electrostrictive multimaterial PMN-PT monomorph actuators,” Journal of the European Ceramic Society, vol. 25, no. 12, pp. 2991–2997, 2005. View at Publisher · View at Google Scholar
  57. M. S. Zarnik, D. Belavic, and S. Macek, “Evaluation of the constitutive material parameters for the numerical modelling of structures with lead-zirconate-titanate thick films,” Sensors and Actuators A, vol. 136, no. 2, pp. 618–628, 2007. View at Publisher · View at Google Scholar
  58. H. Park and D. A. Horsley, “MEMS deformable mirrors for adaptive optics using single crystal PMN-PT,” in Proceedings of IEEE/LEOS International Conference on Optical MEMS and Nanophotonics (OPT MEMS '08), pp. 90–91, August 2008. View at Publisher · View at Google Scholar
  59. W. K. Wilkie, D. J. Inman, J. M. Lloyd, and J. W. High, “Anisotropic laminar piezocomposite actuator incorporating machined PMN-PT single-crystal fibers,” Journal of Intelligent Material Systems and Structures, vol. 17, no. 1, pp. 15–28, 2006. View at Publisher · View at Google Scholar
  60. P. Ngernchuklin, E. K. Akdoǧan, and A. Safari, “Piezoelectric-electrostrictive monolithic bi-layer composite flextensional actuator,” IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control, vol. 56, no. 6, Article ID 5075095, pp. 1131–1138, 2009. View at Publisher · View at Google Scholar · View at PubMed