Microstructure and piezoelectric properties of (Na0.5K0.5)NbO3 lead-free piezoelectric ceramics with V2O5 addition

IEEE Trans Ultrason Ferroelectr Freq Control. 2009 Nov;56(11):2337-42. doi: 10.1109/TUFFC.2009.1321.

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.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Ceramics / chemistry*
  • Equipment Design
  • Equipment Failure Analysis
  • Materials Testing
  • Micro-Electrical-Mechanical Systems / instrumentation*
  • Transducers*
  • Vanadium Compounds / chemistry*
  • Vibration

Substances

  • Vanadium Compounds
  • vanadium pentoxide