Enhanced electrical properties in lead-free NBT–BT ceramics by series ST substitution. Issue 7 (15th May 2016)

• Record Type: Journal Article
• Authors: Cao, W.P.; Li, W.L.; Bai, T.R.G.L.; Yu, Y.; Zhang, T.D.; Hou, Y.F.; Feng, Y.; Fei, W.D.
• Is Part Of: Ceramics international. Volume 42:Issue 7(2016)
• Page Start: 8438
• Page End: 8444
• Publication Date: 2016-05-15
• Subjects: NBT-based ceramics -- Piezoelectric property -- Electrocaloric effect -- Electric-field-induced strain; Ceramics -- Periodicals; Céramique industrielle -- Périodiques; Ceramics; Periodicals; Electronic journals; 666
• DOI: 10.1016/j.ceramint.2016.02.063
• Languages: English
• ISSNs: 0272-8842

Abstract

Abstract: Comprehensive electrical properties of 0.94(Na1/2 Bi1/2 )TiO3 –0.06BaTiO3 lead-free ceramics by doping series SrTiO3 were investigated. High piezoelectric constant of 205 pC/N and electromechanical coupling factor of 0.34 were obtained due to the forming of the rhombohedral–tetragonal morphotropic phase boundary at x =0.02–0.06. Very large recoverable strain of 0.34% was obtained at x =0.10 due to the coexistence of ferroelectric and relaxor pseudocubic phases. A large electrocaloric effect (Δ T max =1.71 K and Δ T /Δ E =0.34 K mm kV −1 at 50 kV cm −1 ) which determined by indirect measurements method was obtained at 120 °C at x =0.02, which is significantly higher than that of lead-free ferroelectric ceramics reported so far. Moreover, lower operating temperatures of 50 °C and 30 °C were proposed when x =0.10 and 0.20 with Δ T max =0.79 K and 0.6 K, respectively. These properties added together indicate a promising material for applications in cooling systems and actuators.