Detection of phase transitions in sodium bismuth titanate–barium titanate single crystals by acoustic emission

Abstract

Acoustic emission measurements are combined with strain, dielectric, and polarization measurements to detect phase transitions in 0.94Na0.5Bi0.5TiO3–0.06BaTiO3 single crystals during thermal cycling as well as electric field cycling at both room temperature and 140°C. All phase transitions known from the literature (cubic↔tetragonal↔trigonalI↔trigonalII) are determined to be of first order, and the existence of the ferroelectric trigonal II phase at room temperature and its transformation into an antiferroelectric phase during heating above 130°C is established.

Influence of electric fields on the depolarization temperature of Mn-doped (1-x)Bi1/2Na1/2TiO3-xBaTiO3

“…Obviously, the temperature range of ferroelectric behavior can be extended by external bias fields. This is in agreement with acoustic emission data obtained from undoped BNT-6BT, which shows that a field of 850 V/mm can induce long-range order and remanent polarization, respectively, at 140 C. 38 The diffuse maxima observed in the TSDC of BNT-6BT:Mn and BNT-9BT:Mn in contrast to BNT-3BT:Mn (Fig. 3) indicate that the stepwise depolarization is a result of the mixed phase structure.…”

Low temperature preparation and electrical properties of sodium–potassium bismuth titanate lead-free piezoelectric thick films by screen printing

“…30 In recent years, more and more researchers found the antiferroelectric phase in NBT based materials at the temperature higher than that transition. Dul'kin et al 31 detected ferroelectric to antiferroelectric phase transation in NBT based single crystals by acoustic emission. Moreover, using TEM and SAED measurement, Dorcet and Trolliard 32,33 believed ferroelectric to antiferroelectric and antiferroelectric to paraelectric transitions occurred near 200 and 320 • C, respectively.…”

Growth and electrical properties of 0.95Na0.5Bi0.5TiO3–0.05K0.5Bi0.5TiO3 lead-free piezoelectric crystal by the TSSG method

“…Since sodium bismuth titanate, Na 0.5 Bi 0.5 TiO 3 (NBT), an A-site complex perovskite ferroelectric was discovered by Smolenskii in 1960 [1,2], NBT and NBT-based solid solutions, such as (Na 0.5 Bi 0.5 )TiO 3 -(K 0.5 Bi 0.5 )TiO 3 and (Na 0.5 Bi 0.5 )TiO 3 -BaTiO 3 , have been actively investigated as possible substitute for lead-based piezoelectric materials from the viewpoint of environmental protection [3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19][20][21]. Among them, (1À x)(Na 0.5 Bi 0.5 )TiO 3 -x(K 0.5 Bi 0.5 )TiO 3 (abbreviated as (1À x)NBT-xKBT) is one of the most attractive system due to their excellent piezoelectric properties [12][13][14][15][16][17][18][19][20][21][22].…”