Barium titanate single crystal

This kind of microstructure also influences other kinds of conductors, especially those with positive (PTC) or negative (NTC) temperature coefficients of resistivity. For instance, PTC materials (Kulwicki 1981) have to be impurity-doped polycrystalline ferroelectrics, usually barium titanate (single crystals do not work) and depend on a ferroelectric-to-paraelectric transition in the dopant-rich grain boundaries, which lead to enormous increases in resistivity. Such a ceramic can be used to prevent temperature excursions (surges) in electronic devices. 

Remeika, J.P. (1954) A method for growing barium titanate single crystals. J. Am. 

Remeika, l.P. (1954) A method for growing barium titanate single crystals, J. Am. Chem. Soc. 76, 940. Growth of BaTiOj by flux growth at Bell Labs. 

Yamamoto T, Sakuma T (1994) Fabrication of barium titanate single-crystals by solid-state grain-growth. J Am Ceram Soc 77 1107-1109... 

Rehrig, P. W., Messing, G. L. and Trolier-McKinstry, S., Templated grain growth of barium titanate single crystals, J. Am. Ceram. Soc., 83, 2654-60, 2000. 

Misarova, A. (1960) Aging of barium titanate single crystals. Solid State Phys., 2 (6), 1160-1165. 

P.W.Rehrig, S.Park, S.Trolier-McKinstry, G.L.Messing, B.Jones, T.Shrout Piezoelectric properties of zirconium-doped barium titanate single crystals grown by templated grain growth J. 

Figure 9.23 Optical micrograph of a barium titanate single crystal growing into a polycrystalline matrix after annealing for 20 h at 1300°C. (From Ref 36.)...

Because barium titanate has interesting properties, many methods have been used to grow single crystals of this compound. One of the most popular techniques, using a potassium fluoride flux, was first employed by Remeika.1... 

Another circumstance is when deterioration becomes apparent under fields in excess of 0.5 MVm-1 at temperatures above 85 °C, and occurs more rapidly the higher the field or the temperature. The fall in resistance has been observed in single crystals of rutile and barium titanate and so must be assumed to be a bulk rather than a grain boundary effect, although there is evidence that grain boundaries play a part in degradation processes in ceramics. 

Barium titanate crystals rank high among those solids on which electronic research has been focused during the last two decades, because this compound and its derivatives belong to a promising group of ferroelectrics. The properties of single crystals of BaTiOs reveal that the crystals are not uniform they respond to an electrical field as if they have a skin which covers the bulk of the crystal. 

Barium titanate is ferroelectric and, by implication, also pyroelectric and piezoelectric. The characteristic of a ferroelectric is that it is polarized in the absence of an applied electric field and the direction of polarization can be reversed. Figure 31.10 shows a rectangular hysteresis loop for a singledomain single crystal of BaTiOs. This loop was obtained at room temperature using a 50 Hz supply. 

ON THE INFLUENCE OF A DC FIELD ON THE THERMAL CONDUCTIVITY OF BARIUM TITANATE BASE CERAMIC SPECIMENS AND TRIGLYCINE SULFATE SINGLE CRYSTALS IN THE PHASE TRANSITION REGION. //ENGLISH TRANSLATION OF IZV. AKAD. NAUK SSSR, SER. FIZ. 31 /11/1842-4,... 

EFFECT OF A CONSTANT ELECTRIC FIELD ON THE THERMAL CONDUCTIVITY OF CERAMIC SAMPLES OF SOLID SOLUTIONS BASED ON BARIUM TITANATE AND OF A TRIGLYCINE SULFATE SINGLE CRYSTAL IN THE REGION OF PHASE TRANSITIONS. 

Barium titanate has been studied extensively since the end of World War II when it was identified independently in Russia, Japan and USA as a promising material with high permittivity for ceramic capacitors. Its ferroelectric activity is known since 1946 when it was discovered on ceramic samples. Since 1950 s also the single-crystals of desired size and quality are available. BaTiOs undergoes several phase transitions... 

The diffusion characteristics of Ni ions were evaluated in non-doped, Ho-doped polycrystalline and single-crystal barium titanate perovskite using secondary ion mass spectrometry. The bulk diffusion coefficients of Ni at 1100 to 1400C were described by ... 

Figure 8.5 Hysteresis loop for a single-domain single crystal of barium titanate (Moulson and Herbert, 2003). Reprinted with permission from Wiley-Blackwell Ltd, Oxford, UK.

J.4.2 Materials Barium strontium titanate (BST) is one of the many ferroelectric materials. The ratio of Ba Sr can be varied this ratio can be expressed as (0.65 0.35) or more completely Bao.gsSro jsTiOj. According to Aggarwal (2010), BST ceramic and single crystals have the highest p ever obtained from pyroelectic materials (23 x 10 Cb/(cm K). 

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