Materials for high temperature acoustic and vibration sensors: A review

Temperature dependence of piezoelectric properties of high-TC Bi(Mg1/2Ti1/2)O3–PbTiO3

“…͑1−x͒Bi͑Mg 1/2 Ti 1/2 ͒O 3 -xPbTiO 3 ͑abbreviated as BMT-PT100x͒ ceramics of three compositions ͑x = 0.36, 0.37, and 0.38͒ were prepared by the conventional solid-state reaction method. MgTiO 3 was first synthesized as a precur-sor at 1400°C for 4 h using reagent graded oxide precursors 13,15 and then mixed with PbO ͑99.9%, Alfa Aesar͒, TiO 2 ͑99.9%, Alfa Aesar͒, and Bi 2 O 3 ͑99.975%, Alfa Aesar͒ according to the stoichiometric formulas of each composition.…”

“…[1][2][3] The operating temperature of piezoelectric ceramics is generally limited to one-half of the Curie point ͑T C ͒ due to loss of polarization, typically at temperatures lower than 200°C ͓e.g., 150°C for the conventional piezoelectric materials based on the Pb͑Zr 1−x Ti x ͒O 3 ͑PZT͔͒ with a Curie temperature, T C = 386°C. 4 After excellent piezoelectric properties for ͑1 − x͒BiScO 3 -xPbTiO 3 ͑BS-PT͒ near the morphotropic phase boundary ͑MPB͒ ͑x = 0.64͒ were reported ͑piezoelectric coefficient, d 33 = 460 pC/ N, planar coupling coefficient, k p = 0.56, and T C = 450°C͒ recently, 5,6 the discovery of several promising high temperature piezoelectric materials with high performance followed in the general BiMeO 3 -PbTiO 3 system, [5][6][7][8][9][10][11][12][13][14][15][16][17][18][19][20][21][22][23][24] where Me can be a single cation of valency +3 ͑e.g., Sc 3+ and Fe 3+ ͒ or a mixture of cations with an average valence of +3 ͑e.g., Mg 1/2 Ti 1/2 and Ni 2/3 Nb 1/3 ͒. It has been proposed that the Bi substitution plays an unusual role of considerable enhancement of both Curie temperature ͑T C ͒ and tetragonality ͑c / a͒, which results from a strong coupling between Pb/Bi cations and B-site cations of strong ferroelectric activity, such as Ti, Zn, and Fe.…”

Domain switching energies: Mechanical versus electrical loading in La-doped bismuth ferrite–lead titanate

“…[1][2][3] A significant amount of the materials used in these applications are polycrystalline ferroelectrics with perovskite structure, such as PZT. These materials exhibit significant nonlinearity primarily caused by domain wall motion.…”

“…4,5 The achievable strain is thus closely correlated to the spontaneous strain, e.g., the tetragonal distortion, of the perovskite crystal structure. This implies for certain applications such as high temperature actuators, 1,6,7 where PZT is not ideal due to its relatively low Curie temperature, that a large tetragonality would be beneficial. There are, however, certain limitations.…”

Dynamic thermal/acoustic response for human bone materials at different energy levels: A diagnosis approach

“…A change within 1.5 K is high enough to monitor via IR based sensors. 15 Piezoelectric material 16 may also be utilized for measuring the acoustic vibration within the bone material. The idea of the practical model is shown in Fig.…”