title: Microstructure and piezoelectric properties of (Na0.5K0.5)NbO3 lead-free piezoelectric ceramics with V2O5 addition.
abstract: Various amounts of Nb(2)O(5) in the (Na(0.5)K(0.5)) NbO(3) (NKN) ceramic were replaced by V(2)O(5) to decrease its sintering temperature to below 950 degrees C. A small V(2)O(5) content resulted in a dense microstructure with an increased grain size for the specimen sintered at 900 degrees C due to the presence of a liquid phase. When V(2)O(5) was added to the NKN ceramics, their orthorhombic-to-tetragonal transition temperature increased from 178 degrees C to around 200 degrees C. However, their Curie temperature decreased from 402 degrees C to around 330 degrees C. The k(p), epsilon(3) (T)/epsilon(0), and Q(m) values increased with V(2)O(5) addition, probably due to the increased density and poling state, which was identified by the phase angle. The specimen with x = 0.05, sintered at 900 degrees C for 8 h, exhibited the following piezoelectric properties: k(p) = 0.32, epsilon(3) (T)/epsilon(0) = 245, d(33) = 120 (pC/N), and Q(m) = 232.
authors: Department of Materials Science and Engineering, Korea University, Seoul, Korea.
authors: In-Tae
authors: IT
authors: Seo
authors: Hwi-Yeol
authors: HY
authors: Park
authors: Van Dung
authors: VD
authors: Nguyen
authors: Min-Kyu
authors: MK
authors: Choi
authors: Sahn
authors: S
authors: Nahm
authors: Hyeung-Gyu
authors: HG
authors: Lee
authors: Byung-Hyun
authors: BH
authors: Choi
mesh_terms: D002516:Ceramics / Q000737:chemistry*; D004867:Equipment Design; D019544:Equipment Failure Analysis; D008422:Materials Testing; D055617:Micro-Electrical-Mechanical Systems / Q000295:instrumentation*; D014159:Transducers; D017968:Vanadium Compounds / Q000737:chemistry*; D014732:Vibration
chemical_list: D017968:Vanadium Compounds; C066075:vanadium pentoxide