Anisotropy Factors and Electromechanical Coupling in Lead-Free 1–3-Type Composites

Volume Fraction ◽

Piezoelectric Materials ◽

Lead Free ◽

Aspect Ratios ◽

Polymer Component ◽

Coupling Factors

The effective electromechanical properties andanisotropy factors of novel lead-free 1–3-type compositesare studied to demonstrate their large piezoelectricanisotropy and considerable level of electromechanicalcoupling. The composites studied contain two single-crystal components and a polymer component. The firstpiezo-active component is a domain-engineered [001]-poled single crystal based on ferroelectric alkali niobates-tantalates, and this component is in the form of a system oflong rods that are parallel to the poling axis OX3. Thesecond single-crystal component is a system of spheroidalpiezoelectric Li2B4O7 inclusions aligned in a continuousand relatively large polymer matrix. The single-crystalrods are surrounded by a single crystal / polymer matrix,and the connectivity of the composite is 1–0–3. It is shownthat the conditions d * /| d * | 3 5, which indicates a large 33 31degree of anisotropy of the piezoelectric coefficients, and k* /|k* |35and k*/|k*|35,whichindicatealargeanisotropyof the electromechanical coupling factors, can be achievedsimultaneously in specific ranges of the component volumefractions and inclusion aspect ratios. Moreover, in thesame volume-fraction and aspect-ratio ranges, largeelectromechanical coupling factors (k* » k* » 0.8–0.9) are 33 talso achieved. In this context, the important role of the elastic properties of the continuous anisotropic matrix is discussed. The properties and anisotropy factors of the lead-free 1–3-type composites are compared to similar parameters of conventional lead-containing piezoelectric materials, and the advantages of the composite system studied are described.

Hydrostatic piezoelectric parameters of lead-free 2–0–2 composites with two single-crystal components: Waterfall-like orientation dependences

Journal of Advanced Dielectrics ◽

10.1142/s2010135x20500150 ◽

2020 ◽

Vol 10 (04) ◽

pp. 2050015

Author(s):

Vitaly Yu. Topolov ◽

Ashura N. Isaeva

Keyword(s):

Single Crystal ◽

Volume Fraction ◽

Elastic Anisotropy ◽

Coupling Factor ◽

Lead Free ◽

Crystallographic Axis ◽

Crystal Layer ◽

Single Crystal Layer

A system of hydrostatic parameters is studied in novel 2–0–2 composites that contain two lead-free piezoelectric single-crystal components. The ferroelectric domain-engineered alkali niobate-tantalate-based single-crystal layer promotes large values of the piezoelectric coefficients [Formula: see text] and [Formula: see text], hydrostatic squared figure of merit [Formula: see text], and hydrostatic electromechanical coupling factor [Formula: see text] of the composite wherein the 0–3 Li2B4O7 single crystal/polyethylene layers are adjacent to the aforementioned single-crystal layer. Hereby, the role of the elastic anisotropy of the 0–3 layer is emphasized. An orientation effect concerned with rotations of the crystallographic axes of the piezoelectric Li2B4O7 single crystal in the 0–3 layer is first studied. It is shown that the orientation of the crystallographic axis [Formula: see text] of the Li2B4O7 single crystal in the polymer matrix strongly influences the piezoelectric properties and hydrostatic parameters of the composite. Examples of the so-called waterfall-like orientation dependences of the hydrostatic parameters are analyzed. The composite based on the domain-engineered [Lix([Formula: see text][Formula: see text]]([Formula: see text][Formula: see text]O3:Mn single crystal is of interest due to [Formula: see text][Formula: see text]mV[Formula: see text]m/N, [Formula: see text] Pa[Formula: see text], and [Formula: see text]–0.75 in the studied volume-fraction and orientation ranges, and these hydrostatic parameters are to be taken into account in the field of piezotechnical, hydroacoustic, and energy-harvesting applications.

The Characteristic of the La3Ga5SiO14 Single Crystal Grown by Vertical Bridgman Method in Ar Atmosphere

Materials Science Forum ◽

10.4028/www.scientific.net/msf.510-511.842 ◽

2006 ◽

Vol 510-511 ◽

pp. 842-845 ◽

Cited By ~ 5

Author(s):

Noriko Bamba ◽

Kentaro Kato ◽

Toshinori Taishi ◽

Takayuki Hayashi ◽

Keigo Hoshikawa ◽

...

Keyword(s):

Melting Point ◽

Single Crystal ◽

Single Crystals ◽

Room Temperature ◽

Color Change ◽

Piezoelectric Materials ◽

Lead Free ◽

Piezoelectric Constant ◽

Interstitial Oxygen ◽

Vertical Bridgman

Langasite (La3Ga5SiO14: denoted by LGS) single crystal is one of the lead free piezoelectric materials with high piezoelectricity that is maintained up to its melting point (1470°C). Although LGS single crystals have usually been grown by Czochralski (CZ) method in oxygen contained atmosphere to prevent evaporation of Ga, they were grown by the vertical Bridgman (VB) method in Ar atmosphere without oxygen, and their properties were evaluated in this work. Transparent and colorless LGS single crystals were successfully obtained without Ga evaporation by the VB method in Ar atmosphere, and their resistivity at room temperature was much higher than that grown by conventional CZ method. Piezoelectric constant d11 of the crystal grown by the VB method was 6 x 10-12 C/N, which was close to that of the crystal grown by CZ method. The colorless transparent LGS single crystal turned to orange and its resistivity decreased by annealing in air. Since an orange-colored transparent LGS single crystal has been grown by conventional CZ method, this indicates that color change and the resistivity decrease of LGS crystal is caused by extra interstitial oxygen atoms in the crystal.

Effect of the matrix subsystem on hydrostatic parameters of a novel 1–3-type piezo-composite

Functional Materials Letters ◽

10.1142/s1793604715500496 ◽

2015 ◽

Vol 08 (05) ◽

pp. 1550049 ◽

Cited By ~ 8

Author(s):

Vitaly Yu. Topolov ◽

Christopher R. Bowen ◽

Paolo Bisegna ◽

Anatoly E. Panich

Keyword(s):

Elastic Properties ◽

Volume Fraction ◽

Ferroelectric Ceramic ◽

Coupling Factor ◽

Polyurethane Composite ◽

The Matrix ◽

Type Composite

The influence of the aspect ratio and volume fraction of ferroelectric ceramic inclusions in a 0–3 matrix on the hydrostatic parameters of a three-component 1–3-type composite is studied to demonstrate the important role of the elastic properties of the two-component matrix on the composite performance. Differences in the elastic properties of the 0–3 matrix and single-crystal rods lead to a considerable dependence of the hydrostatic response of the composite on the anisotropy of the matrix elastic properties. The performance of a 1–0–3 0.92 Pb ( Zn 1/3 Nb 2/3) O 3–0.08 PbTiO 3 SC/modified PbTiO 3 ceramic/polyurethane composite suggests that this composite system is of interest for hydroacoustic applications due to its high hydrostatic piezoelectric coefficients [Formula: see text] and [Formula: see text], squared figure of merit [Formula: see text], and electromechanical coupling factor [Formula: see text].

Comparative study on the performance of piezo-active 1–3-type composites with lead-free components

Journal of Advanced Dielectrics ◽

10.1142/s2010135x21600031 ◽

2021 ◽

pp. 2160003

Author(s):

Ashura N. Isaeva ◽

Vitaly Yu. Topolov

Keyword(s):

Single Crystal ◽

Piezoelectric Coefficient ◽

Piezoelectric Properties ◽

Volume Fraction ◽

Lead Free ◽

Figures Of Merit ◽

Piezoelectric Energy ◽

Harvesting Systems ◽

Porous Matrices ◽

Large Anisotropy

Piezoelectric properties and related figures of merit are studied in novel 1–3-type composites based on ferroelectric domain-engineered lead-free single crystal with the relatively large longitudinal piezoelectric coefficient [Formula: see text]. Relationships between the piezoelectric properties and the set of figures of merit are analyzed for the 1–3 and 1–3–0 composites that contain the same single-crystal and polymer components. For a composite characterized by 1–3–0 connectivity, an influence of a porous piezo-passive matrix on the figures of merit and their volume-fraction behavior is considered additionally. A large anisotropy of figures of merit is observed in the 1–3–0 composite with specific porous matrices. A diagram is put forward to show volume-fraction regions of the large anisotropy of figures of merit of the studied 1–3–0 composite. Due to large figures of merit and their considerable anisotropy, the studied lead-free composites can be applied in piezoelectric energy-harvesting systems, sensors, transducers, and so on.

Enhanced fatigue resistance and lattice dynamics induced by the strong local strain in Fe-doped KTa1-xNbxO3 single crystal

Journal of Materials Chemistry C ◽

10.1039/d1tc04480j ◽

2021 ◽

Author(s):

Xiaolin Huang ◽

Peng Tan ◽

Yu Wang ◽

Yao Zhang ◽

Xiangda Meng ◽

...

Keyword(s):

Single Crystal ◽

Fatigue Resistance ◽

Lattice Dynamics ◽

Piezoelectric Materials ◽

Local Strain ◽

Lead Free ◽

Fatigue Properties ◽

Practical Applications ◽

Local Structures ◽

The Impact

Improvement of durability is greatly important for the practical applications of lead-free-doped piezoelectric materials. However, the promotional mechanism of anti-fatigue properties and the impact on local structures from ion dopants...

(1-x)(K0.475Na0.475Li0.05)(Nb0.975Sb0.025)O3-xBiFeO3 Lead-Free Piezoelectric Ceramics with CuO Sintering Aid

Materials Science Forum ◽

10.4028/www.scientific.net/msf.687.228 ◽

2011 ◽

Vol 687 ◽

pp. 228-232

Author(s):

Yong Jie Zhao ◽

Yu Zhen Zhao ◽

Rong Xia Huang ◽

Rong Zheng Liu ◽

He Ping Zhou

Keyword(s):

Electrical Properties ◽

Piezoelectric Materials ◽

Piezoelectric Ceramics ◽

Coupling Factor ◽

Mechanical Quality Factor ◽

Lead Free ◽

X Ray Diffraction ◽

Diffraction Patterns

(1-x) (K0.475Na0.475Li0.05)(Nb0.975Sb0.025)O3-xmolBiFeO3 (x=0, 0.002, 0.004, 0.006, 0.008) doped with 0.8mol%CuO lead-free piezoelectric ceramics were prepared by the solid state reaction technique. X-ray diffraction patterns suggested that all the ceramics presented perovskite structure. The compositional dependence of the phase structure and the electrical properties of the ceramics were studied. The ceramic (x=0.002) near room temperature exhibited excellent electrical properties (piezoelectric constant d33=172pC/N, planar electromechanical coupling factor kp=0.43, and dielectric constant =418). A relatively high mechanical quality factor (Qm=200) was also obtained in this particular composition. All these results revealed that this system might become a promising candidate for lead-free piezoelectric materials.

Hydrostatic Parameters and Domain Effects in Novel 2-2 Composites Based on PZN-0.12PT Single Crystals

Smart Materials Research ◽

10.1155/2011/173064 ◽

2011 ◽

Vol 2011 ◽

pp. 1-10

Author(s):

Vitaly Yu. Topolov ◽

Sergei V. Glushanin ◽

Alexander A. Panich

Keyword(s):

Volume Fraction ◽

Elastic Anisotropy ◽

Coupling Factor ◽

Single Domain ◽

Absolute Minimum ◽

Component Orientation ◽

Record Value

A novel 0.88Pb(Zn1/3Nb2/3)O3-0.12PbTiO3 crystal/polymer composite with 2-2 connectivity is studied at variable orientations of spontaneous polarisation vector of the crystal component. Orientation and volume-fraction dependences of the hydrostatic piezoelectric coefficients dh*, eh*, and gh* and hydrostatic electromechanical coupling factor kh* are related to the important role of the piezoelectric and elastic anisotropy of single-domain layers of the 2-2 composite. The record value of |eh∗|≈77 C/m2 near the absolute-minimum point and the correlation between the hydrostatic (eh*) and piezoelectric (e3j*) coefficients and between the hydrostatic (gh*) and piezoelectric (g3j*) coefficients are first established. This discovery is of value for hydrostatic and piezotechnical applications. The hydrostatic performance of the composite based on the single-domain 0.88Pb(Zn1/3Nb2/3)O3-0.12PbTiO3 crystal is compared to the performance of the 2–2 composites based on either the same polydomain crystal or the related single-domain crystal.

Lead Free (Bi, Na)TiO3–BiAlO3 Ceramics for Piezoelectric Application

Journal of Nanoelectronics and Optoelectronics ◽

10.1166/jno.2020.2762 ◽

2020 ◽

Vol 15 (4) ◽

pp. 459-462

Author(s):

Jae-Hoon Ji ◽

Don-Jin Shin ◽

Sang-Kwon Lee ◽

Sang-Mo Koo ◽

Jae-Geun Ha ◽

...

Keyword(s):

Piezoelectric Properties ◽

Piezoelectric Materials ◽

Lead Free ◽

Electromechanical Coupling Coefficient ◽

Substitution Effects ◽

Sensors And Actuators ◽

Device Applications ◽

Piezoelectric Devices ◽

Piezoelectric Charge

In this research, substitution effects of BiAlO3 with (Bi, Na)TiO3 piezoelectric ceramics was investigated for the sensors and actuators applications. (Bi,Na)TiO3 material has been employed for the piezoelectric devices applications because of their high piezoelectric charge constant, d33, of 88 pC/N, electromechanical coupling coefficient, kp, of 22% and inverse piezoelectric charge constant of 498 pm/V. As a piezoelectric material, (Bi, Na)TiO3 has perovskite structure with tetragonal basis. The improvement of piezoelectric and inverse piezoelectric properties is important for industrial device applications. Therefore, in this research, we have tried to increase functional and electrical properties of (Bi, Na)TiO3 piezoelectric materials by substituting BiAlO3 dopants. As a result, the piezoelectric constant was increased up to 140 pC/N, and the densification was increased up to 5.92 g/cm3 .