采用传统陶瓷工艺制备了(Ag_(0.75)Li_(0.1)Na_(0.1)K_(0.05))(Nb_(1-x)Sb_x)O_3(x=0~0.10)系无铅压电陶瓷,研究了Sb含量变化对陶瓷的相结构、显微结构和电性能的影响。结果表明:在所研究组成范围内陶瓷均形成了单一钙钛矿结构,当x=0.03...采用传统陶瓷工艺制备了(Ag_(0.75)Li_(0.1)Na_(0.1)K_(0.05))(Nb_(1-x)Sb_x)O_3(x=0~0.10)系无铅压电陶瓷,研究了Sb含量变化对陶瓷的相结构、显微结构和电性能的影响。结果表明:在所研究组成范围内陶瓷均形成了单一钙钛矿结构,当x=0.03~0.06时陶瓷存在正交-伪立方两相共存区;Sb^(5+)的引入使陶瓷的晶粒尺寸有所减小,当x=0.04~0.06时陶瓷晶粒尺寸较为均匀(1~2μm)。陶瓷压电常数d_(33)和机电耦合系数k_p随Sb含量增加均先增大后减小,d_(33)和k_p分别在x=0.04和0.05时达到最大值68 p C/N和26.0%。Sb^(5+)的引入使陶瓷的居里温度有所降低,铁电相变得更加不稳定。展开更多
CuO-doped（Ag0.75Li0.1Na0.1K0.05）NbO3（ALNKN-xCuO, x = 0.2mol%） lead-free piezoelectric ceramics were prepared by the solid-state reaction method in air atmosphere. The effects of CuO addition on the phase structure...CuO-doped（Ag0.75Li0.1Na0.1K0.05）NbO3（ALNKN-xCuO, x = 0.2mol%） lead-free piezoelectric ceramics were prepared by the solid-state reaction method in air atmosphere. The effects of CuO addition on the phase structure, microstructure, and piezoelectric properties of the ceramics were investigated. The experimental results show that the ALNKN ceramics without doping CuO possess rhombohedral phase along with K2NbrO16- type phase and metallic silver phase. For all of the CuO-doped ALNKN ceramics, a pure perovskite structure with the orthorhombic phase was obtained by enclosing the samples in a corundum tube. A homogeneous microstructure with＇the grain size of about 1 ~tm was formed for the ceramics with 0.5mo1% CuO. The grain size increases with increasing amount of CuO. The temperature dependence of dielectric properties indicates that the ferroelectric phase of the ALNKN-xCuO ceramics becomes less stable with the addition of CuO. The ceramics with x = lm01% exhibit relatively good electrical properties along with a high Curie temperature. These results will provide a helpful guidance to preparing other AN-based ceramics by solid-state reaction method in air atmosphere.展开更多
Pure Ko.sNao sNbO3(KNN)and KNN doped with Lit(6%mole),Lat(1.66%,5%,6%mole),and Ti+t(10%mole)were prepared by mixture of oxides using high-energy milling and conventional solid-state reaction.The effects of the dopant ...Pure Ko.sNao sNbO3(KNN)and KNN doped with Lit(6%mole),Lat(1.66%,5%,6%mole),and Ti+t(10%mole)were prepared by mixture of oxides using high-energy milling and conventional solid-state reaction.The effects of the dopant on the physical properties of pure KNN have been evaluated based on the structural,ferroelectric,pyroelectric,and dielectric measurements.The XRD measurements show that KNN pure sample contains a mixture of monoclinic and orthorhombic crystalline phases,with a slightly higher concentration of monoclinic phase.In contrast,all doped samples show a higher concentration of the orthorhombic phase,as well as the presence of a secondary phase(K6Nb10.8O3o),also detected by Raman measurements.The samples with a higher concentration of this secondary phase,also present greater dielectric losses and lower values of remnant polarization.The dielectric measurements allowed us to detect temperatures of structural transitions(orthorhombic-tetragonal,O-T)previous to the ferroelectric paraelectric transition(tetragonal-cubic,T-C),and also in this set of samples,a direct correlation was found between the values of remnant polarization and the corresponding pyroelectric signal response.展开更多
文摘采用传统陶瓷工艺制备了(Ag_(0.75)Li_(0.1)Na_(0.1)K_(0.05))(Nb_(1-x)Sb_x)O_3(x=0~0.10)系无铅压电陶瓷,研究了Sb含量变化对陶瓷的相结构、显微结构和电性能的影响。结果表明:在所研究组成范围内陶瓷均形成了单一钙钛矿结构,当x=0.03~0.06时陶瓷存在正交-伪立方两相共存区;Sb^(5+)的引入使陶瓷的晶粒尺寸有所减小,当x=0.04~0.06时陶瓷晶粒尺寸较为均匀(1~2μm)。陶瓷压电常数d_(33)和机电耦合系数k_p随Sb含量增加均先增大后减小,d_(33)和k_p分别在x=0.04和0.05时达到最大值68 p C/N和26.0%。Sb^(5+)的引入使陶瓷的居里温度有所降低,铁电相变得更加不稳定。
基金Funded by the Scientific Research Fund of Sichuan Provincial Education Department(No.11ZB109)
文摘CuO-doped（Ag0.75Li0.1Na0.1K0.05）NbO3（ALNKN-xCuO, x = 0.2mol%） lead-free piezoelectric ceramics were prepared by the solid-state reaction method in air atmosphere. The effects of CuO addition on the phase structure, microstructure, and piezoelectric properties of the ceramics were investigated. The experimental results show that the ALNKN ceramics without doping CuO possess rhombohedral phase along with K2NbrO16- type phase and metallic silver phase. For all of the CuO-doped ALNKN ceramics, a pure perovskite structure with the orthorhombic phase was obtained by enclosing the samples in a corundum tube. A homogeneous microstructure with＇the grain size of about 1 ~tm was formed for the ceramics with 0.5mo1% CuO. The grain size increases with increasing amount of CuO. The temperature dependence of dielectric properties indicates that the ferroelectric phase of the ALNKN-xCuO ceramics becomes less stable with the addition of CuO. The ceramics with x = lm01% exhibit relatively good electrical properties along with a high Curie temperature. These results will provide a helpful guidance to preparing other AN-based ceramics by solid-state reaction method in air atmosphere.
基金The authors express their thanks to CONACYT for funding this research through projects CB-240460 and LN-295261,and to LIDTRA for the facilities in the use of experimental infrastructure.
文摘Pure Ko.sNao sNbO3(KNN)and KNN doped with Lit(6%mole),Lat(1.66%,5%,6%mole),and Ti+t(10%mole)were prepared by mixture of oxides using high-energy milling and conventional solid-state reaction.The effects of the dopant on the physical properties of pure KNN have been evaluated based on the structural,ferroelectric,pyroelectric,and dielectric measurements.The XRD measurements show that KNN pure sample contains a mixture of monoclinic and orthorhombic crystalline phases,with a slightly higher concentration of monoclinic phase.In contrast,all doped samples show a higher concentration of the orthorhombic phase,as well as the presence of a secondary phase(K6Nb10.8O3o),also detected by Raman measurements.The samples with a higher concentration of this secondary phase,also present greater dielectric losses and lower values of remnant polarization.The dielectric measurements allowed us to detect temperatures of structural transitions(orthorhombic-tetragonal,O-T)previous to the ferroelectric paraelectric transition(tetragonal-cubic,T-C),and also in this set of samples,a direct correlation was found between the values of remnant polarization and the corresponding pyroelectric signal response.
