Large thickness-mode electromechanical coupling and good temperature stability of 1–3 PZT/epoxy composites

Author(s):  
Chunming Zhou ◽  
Jialiang Zhang ◽  
Wenbin Su ◽  
Yue Cao
2013 ◽  
Vol 479-480 ◽  
pp. 3-7
Author(s):  
Chun Huy Wang

In the present study, various quantities of Bi2O3were added into 0.98(Na0.5K0.5)NbO3-0.02Bi(Na0.93K0.07)TiO3(0.98NKN-0.02BNKT) ceramics. It was found that 0.98NKN-0.02BNKTwith the addition of 0~0.5 wt.% Bi2O3exhibit relatively good piezoelectric properties. For 0.98NKN-0.02BNKT ceramics, the electromechanical coupling coefficients of the planar modekpand the thickness modektreach 0.40 and 0.47,respectively. For 0.98NKN-0.02BNKT ceramics with the addition of 0.3 wt.% Bi2O3, the electromechanical coupling coefficients ofthe planar modekpand the thickness modektreach 0.50 and 0.53, respectively. It is obvious that 0.98NKN-0.02BNKT solid solution ceramics by adding low quantities of Bi2O3is one of the promising lead-free ceramics for electromechanical transducer applications.


2013 ◽  
Vol 368-370 ◽  
pp. 760-763
Author(s):  
Chun Huy Wang ◽  
Ming Qiu Wei

(Na0.5K0.5)NbO3 with Bi0.5(Na0.97K0.03)0.5TiO3 with x≤0.05 has been prepared by the conventional mixed oxide process. X-ray diffraction analysis revealed that, during sintering, all the Bi(Na0.97K0.03)TiO3 diffuses into the lattice of (Na0.5K0.5)NbO3 to form a solid solution with a perovskite structure. A morphotropic phase boundary (MPB) between orthorhombic (O) and rhombohedral (R) was found at the composition 0.98(Na0.5K0.5)NbO3-0.02Bi0.5(Na0.97K0.03)0.5TiO3 [abbreviated as 0.98NKN-0.02BNKT] with correspondingly enhanced dielectric and piezoelectric properties. For 0.98NKN-0.02BNKT ceramics, the electromechanical coupling coefficients of the planar mode kp and the thickness mode kt reach 0.33 and 0.49, respectively, after sintering at 1100 oC for 3 h. The ratio of the thickness coupling coefficient to the planar coupling coefficient is 1.48. With suitable Bi0.5(Na0.97K0.03)0.5TiO3 concentration, a dense microstructure and good electrical properties are obtained.


2010 ◽  
Vol 434-435 ◽  
pp. 413-416 ◽  
Author(s):  
Chun Huy Wang

The 0.98(Na0.5K0.5)NbO3–0.02Ba(Zr0.04Ti0.96)O3 ceramics have been prepared following the conventional mixed oxide process. X-ray diffraction analysis revealed that, during sintering, all of the Ba(Zr0.04Ti0.96)O3 diffuses into the lattice of (Na0.5K0.5)NbO3 to form a solid solution, in which a orthorhombic phase with a perovskite structure was found In order to improve the sinterability of the ceramics, Bi2O3 additions were used as a sintering aid. The electromechanical coupling coefficients of the planar mode kp and the thickness mode kt reach 0.3 and 0.55, respectively, at the sintering of 1100oC for 5 h. For 0.98NKN-0.02BZT ceramics by doping 0.5 wt.% Bi2O3, the electromechanical coupling coefficients of the planar mode kp and the thickness mode kt reach 0.21 and 0.57, respectively. The ratio of thickness coupling coefficient to planar coupling coefficient is 2.7.


2007 ◽  
Vol 124-126 ◽  
pp. 53-56
Author(s):  
Sean Wu ◽  
Zhi Xun Lin ◽  
Maw Shung Lee

Langasite (La3Ga5SiO14 or abbreviated as LGS) single crystal is an attractive substrate for surface acoustic wave (SAW) devices requiring good temperature stability and higher electromechanical coupling constant than quartz. AlN thin films are attractive materials that have some excellent characteristics, such as high SAW velocity, piezoelectricity, high-temperature stability, and stable chemical properties. In this study, AlN thin films were deposited on LGS to be a new composite SAW substrate (AlN/LGS) by reactive RF magnetron sputtering method. SAW delay-line device was manufactured on this substrate. The performance of the device was measured by network analyzer (Agilent 8753E).The results exhibited the composite substrate (AlN/LGS) increased the Rayleigh wave velocity, decreased the insertion loss of SAW devices, and suppressed the harmonic response.


2011 ◽  
Vol 130-134 ◽  
pp. 883-886
Author(s):  
Chun Huy Wang

In this paper, the effects of Ta2O5addition on the electrical and physical properties of 0.98(Na0.5K0.5)NbO3-0.02(Na0.5Bi0.5)TiO3were investigated. The 0.98(Na0.5K0.5)NbO3-0.02(Na0.5Bi0.5)TiO3[0.98NKN-0.02NBT] ceramics with the addition of 0~0.5 wt% Ta2O5have been prepared following the conventional mixed oxide process. X-ray diffraction analysis revealed that, during sintering, all of the (Na0.5Bi0.5)TiO3diffuse into the lattice of (Na0.5K0.5)NbO3to form a solid solution, in which a orthorhombic phase with a perovskite structure was found. For 0.98NKN-0.02NBT ceramics by doping 0.1 wt% Ta2O5, the poled dielectric constant (K33T) is 1090. The electromechanical coupling coefficients of the planar modekpand the thickness modektreach 0.39 and 0.48, respectively. Our results show that 0.98NKN-0.02NBT with the addition of 0.1 wt% Ta2O5is a good lead-free piezoelectric ceramic.


2011 ◽  
Vol 415-417 ◽  
pp. 1051-1054
Author(s):  
Chun Huy Wang

In the present study, various quantities of Bi2O3were added into 0.98(Na0.5Bi0.5)TiO3-0.02Ba(Sn0.08Ti0.92)O3(0.98NBT-0.02BST) ceramics. High-density samples were obtained through the addition of Bi2O3into 0.98NBT-0.02BST ceramic. It was found that 0.98NBT-0.02BST with the addition of 0~3.0 wt.% Bi2O3exhibit relatively good piezoelectric properties. For 0.98NBT-0.02BST ceramic with the addition of 2 wt.% Bi2O3, the electromechanical coupling coefficients of the planar mode kp and the thickness mode kt reach 0.12 and 0.61, respectively, at the sintering of 1100oC for 3 h. The ratio of thickness coupling coefficient to planar coupling coefficient is 5.1. It is obvious that 0.98NBT-0.02BST solid solution ceramic by adding low quantities of Bi2O3is one of the promising lead-free ceramics for high frequency electromechanical transducer applications.


2010 ◽  
Vol 434-435 ◽  
pp. 409-412 ◽  
Author(s):  
Chun Huy Wang

In this paper, the effect of Mn2O3 additions on the electrical and physical properties of 0.98(Na0.5Bi0.5)TiO3 -0.02Ba(Sn0.08Ti0.92)O3 was investigated. X-ray diffraction analysis revealed that, during sintering, all of the Ba(Sn,Ti)O3 diffuse into the lattice of (Na0.5Bi0.5)TiO3 to form a solid solution, in which a hexagonal phase with a perovskite structure was found. The 0.98(Na0.5Bi0.5)TiO3 -0.02Ba(Sn0.08Ti0.92)O3 [0.98NBT-0.02BST] ceramics with the addition of 0~4.0 wt% Mn2O3 have been prepared following the conventional mixed oxide process. For 0.98NBT-0.02BST ceramics by doping 1.0 wt% Mn2O3, the electromechanical coupling coefficients of the planar mode kp and the thickness mode kt reach 0.12 and 0.52, respectively, at the sintering of 1100 oC for 3 h. The 0.98NBT-0.02BST ceramic with 1 wt% Mn2O3 addition exhibit a more homogeneous and grain size of ~3.5 μm. With suitable Mn2O3 doping, a dense microstructure and good piezoelectric properties were obtained.


2020 ◽  
Vol 6 (13) ◽  
pp. eaay5979 ◽  
Author(s):  
Chengpeng Hu ◽  
Xiangda Meng ◽  
Mao-Hua Zhang ◽  
Hao Tian ◽  
John E. Daniels ◽  
...  

Electromechanical coupling in piezoelectric materials allows direct conversion of electrical energy into mechanical energy and vice versa. Here, we demonstrate lead-free (KxNa1−x)NbO3 single crystals with an ultrahigh large-signal piezoelectric coefficient d33* of 9000 pm V−1, which is superior to the highest value reported in state-of-the-art lead-based single crystals (~2500 pm V−1). The enhanced electromechanical properties in our crystals are realized by an engineered compositional gradient in the as-grown crystal, allowing notable reversible non-180° domain wall motion. Moreover, our crystals exhibit temperature-insensitive strain performance within the temperature range of 25°C to 125°C. The enhanced temperature stability of the response also allows the materials to be used in a wider range of applications that exceed the temperature limits of current lead-based piezoelectric crystals.


Sign in / Sign up

Export Citation Format

Share Document