40 Result(s)

Article

BaTiO₃ formation by thermal decomposition of a (BaTi)-citrate polyester resin in air

Barium titanate nanosized powders were prepared by a slightly modified Pechini method. The obtained polymerized resin was used as the precursor for BaTiO₃ powder production. DTA TG thermal analysis indicated that...

P. Durán, F. Capel, J. Tartaj, C. Moure in Journal of Materials Research (2001)

Article

Titanium local environment and electrical conductivity of TiO2-doped stabilized tetragonal zirconia

Solid state reactions in the ZrO₂-Y₂O₃-TiO₂system have been studied and the solid solubility limit of TiO₂ in yttria stabilized tetragonal zirconia Y-TZP has been stablished. Structural characterization was carri...

F. Capel, C. Moure, P. Durán, A. R. González-Elipe… in Journal of Materials Science (2000)

Article

Phase transition and electrical conductivity in the system YMnO3-CaMnO3

Solid solution formation between the ferroelectric hexagonal compound YMnO₃ and the semiconducting perovskite compound CaMnO₃ has been studied in the Y-rich region of the pseudobinary system. The materials were p...

C. Moure, M. Villegas, J. F. Fernandez, J. Tartaj, P. Duran in Journal of Materials Science (1999)

Article

Lower air-crystallization temperature and nanostructured yttria-doped tetragonal zirconia polycrystals ceramics by seeding assisted chemical coprecipitation

The crystallization temperature of yttria-doped tetragonal zirconia polycrystals (Y-TZP) amorphous precursors can be lowered 150 °C below that currently used (≥500 °C), if “seeding assisted chemical coprecipit...

P. Durán, J. Tartaj, J. F. Fernández, C. Moure in Journal of Materials Research (1999)

Article

Effects of PbO excess in Pb(Mg_1/3Nb_2/3)O₃–PbTiO₃ ceramics: Part I. Sintering and dielectric properties

The influence of the presence of free PbO on densification, the perovskite/pyrochlore phase ratio, and corresponding dielectric properties has been studied for 0.9 PMN–0.1 PT-based ceramics with different adde...

M. Villegas, A. C. Caballero, M. Kosec, C. Moure… in Journal of Materials Research (1999)

Article

Nanostructured and near defect-free ceramics by low-temperature pressureless sintering of nanosized Y-TZP powders

Nanosized (∼6 nm) Y-TZP (3 mol% Y₂O₃) powders have been produced by chemical co-precipitation (Y-inorganic + Zr-organic precursors) and thorough isopropanol-washing step, after calcining in air at 450 °C. The nan...

P DURAN, M VILLEGAS, F CAPEL, J. F FERNANDEZ, C MOURE in Journal of Materials Science (1997)

Article

Seeding effects on crystallization of air-calcined Y-TZP amorphous precursors

J. TARTAJ, C. MOURE, J. F. FERNANDEZ, P. DURAN in Journal of Materials Science Letters (1997)

Article

Thermal expansion anomalies at the antiferroelectric-- ferroelectric (FRL), ferroelectric (FRL)--ferroelectric (FRH) and ferroelectric (FRH)--paraelectric transitions in PbZr1−xTixO3 (0) < x < 0.35

Abstracts are not published in this journal

B. NOHEDA, J. A. GONZALO, J. DE FRUTOS, A. GONZALEZ… in Journal of Materials Science Letters (1997)

Article

Ceramic–electrode interaction in PZT and PNN–PZT multilayer piezoelectric ceramics with AG/PD 70/30 inner electrode

Pb(Zr0.53Ti0.47)O3(PZT) and PbNi1/3Nb2/3O3-PZT (PNN–PZT) multilayers with Ag/Pd 70/30 inner electrodes have been studied from the point of view of the ceramic–electrode interaction. PZT multilayers have shown ...

A. C Caballero, E Nieto, P Duran, C Moure, M Kosec… in Journal of Materials Science (1997)

Article

Improving sintering behaviour of BaTiO₃ by small do** additions

The dielectric properties of BaTiO₃ ceramics are associated with its microstructure, which depends on the stoichiometric ratio, dopant nature, and ceramic processing. Optimum densification at low temperatures to ...

J. F. Fernández, A. C. Caballero, P. Durán, C. Moure in Journal of Materials Science (1996)

Article

Preparation and sintering behaviour of submicronic Bi₄Ti₃O₁₂ powders

Submicronic powders of Bi₄Ti₃O₁₂ with different morphologies were prepared by both the oxalate coprecipitation and the conventional mixing oxides methods. Compacts of the two calcined powders were sintered at 850...

M. Villegas, C. Moure, J. F. Fernandez, P. Duran in Journal of Materials Science (1996)

Article

Multilayer piezoelectric devices based on PZT

A PZT 53/47 was obtained by a modified chemical route. Small-particle-size powders were allowed to obtain high solid content, non-aqueous slips with Newtonian behaviour. The use of both the tape-casting techni...

E. Nieto, J. F. Fernandez, C. Moure… in Journal of Materials Science: Materials in… (1996)

Article

Low temperature fully densified nanostructured Y TZP ceramics

P. Durán, M. Villegas, F. Lapel, C. Moure in Journal of Materials Science Letters (1996)

Article

Improvement of thermal stability and fracture toughness of Ti-TZP ceramics by small ceria additions

F. Capel, C. Moure, P. Durán in Journal of Materials Science Letters (1996)

Article

Characterization of Pb(Zr, Ti)O₃ thin films obtained by MOD

Pb(Zr, Ti)O₃ thin films were deposited by dip-coating on polycrystalline alumina substrates by using an MOD method. The thickness and homogeneity of the films were measured as a function of dip rates and solution...

E. Nieto, J. F. Fernandez, C. Moure, P. Duran in Journal of Materials Science (1995)

Article

Processing and microstructure of porous and dense PZT thick films on Al₂O₃

The processing of porous PZT thick-film ceramics on Al₂O₃ has been studied. The films were screen-printed from a thixotropic ink of PZT with a 58% solids content. The thick films were sintered between 1000 and 11...

J. F. Fernandez, E. Nieto, C. Moure, P. Duran… in Journal of Materials Science (1995)

Article

Phosphor-doped BaTiO₃: Microstructure development and dielectric properties

The phosphor cation retards BaTiO₃ formation during the first reaction stage, and favours Ba₂TiO₄ formation. As a consequence, the end of the reaction is only accomplished at 1150 °C. The average particle size of...

A. C. Caballero, J. F. Fernández, P. Durán, C. Moure in Journal of Materials Science (1995)

Article

High T_c superconductor polymer composites based on YBa₂Cu₃O_7−x

This work reports on the study of the microstructure and electrical properties (conduction and superconduction) of YBa₂Cu₃O_7−x (Y) and polypropylene (PP) composites. For the purpose of enhancing and improving the...

J. L. Acosta, C. Moure, P. Duran in Journal of Materials Science (1995)

Article

Perovskite phase formation in the PbMg_1/3Nb_2/3 O₃-PbZrO₃-PbTiO₃ system by the columbite route

The reaction mechanism of PbMg_1/3Nb_2/3O₃-PbZrO₃-PbTiO₃ (PMN-PZT) perovskite phase prepared by the columbite route has been studied in the temperature range from 600 to 800 °C. The effects of heating and cooling r...

M. Villegas, J. R. Jurado, C. Moure, P. Duran in Journal of Materials Science (1995)

Article

Microstructure and properties of K₂O doped superconducting YBa₂Cu₃O_7−x

K doped YBa₂Cu₂O_x powders have been obtained by incorporating K₂CO₃ to previously coprecipitated amorphous hydroxide mixtures. Synthesis was performed at 900‡C and an orthorhombic 1 2 3 phase was the final produc...

J. Tartaj, J. F. Fernandez, P. Duran, C. Moure in Journal of Materials Science (1994)