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Partager le résultat de cette recherche Interroger des sources externesLes effets des phases du dioxyde de Titane sur les propriétés structurales et diélectriques des céramiques du type BaTiO3 + x % mole Fe2O3. / Rabah Bounouioua
Titre : Les effets des phases du dioxyde de Titane sur les propriétés structurales et diélectriques des céramiques du type BaTiO3 + x % mole Fe2O3. Type de document : texte imprimé Auteurs : Rabah Bounouioua, Auteur ; Mohmed Tahar Benlahrache, Directeur de thèse Mention d'édition : 15/07/2019 Editeur : جامعة الإخوة منتوري قسنطينة Année de publication : 2019 Importance : 95 f. Format : 30 cm. Note générale : 1 copies imprimées disponibles
Langues : Français (fre) Catégories : Français - Anglais
PhysiqueTags : sciences des matériaux:Céramique BaTiO3 (A) BaTiO3 (R) phases TiO2 phase tétragonale phase hexagonale Propriétés diélectriques TiO2 phases tetragonal phase hexagonal phase dielectrics properties أطوار TiO2 طور رباعي طور سداسي خصائص كهروعزلية Index. décimale : 530 Physique Résumé :
The objective of this investigation is to study the influence of TiO2 phases on the structural and dielectric properties of the BaTiO3 ceramics containing different amounts of Fe2O3. The pure BaTiO3 ceramics was prepared by a solid state reaction between BaCO3 and both of TiO2 phases ; anatase (A) and rutile (R), respectively. We prepared the mixtures by stoichiometric way, which were calcined at 1100 °C during 2hours. The formations of perovskites structures ABO3 were confirmed by X rays diffraction analysis. While the ceramics mixture with (1-x) BaTiO3+ x % Fe2O3 (where x = 1, 2, 5 and 7 wt %) compositions were prepared by the wet milling. Afterwards, the different pellets were fabricated by uniaxial compression and sintered at different temperatures (1300, 1350 and 1400 °C). The obtained results show an increase in the tetragonality due to the doping by Fe3+, consequencely an increase in the relative permittivity of samples prepared from TiO2(R) with both of Fe2O3 addition and sintering temperature. On the other hand, for the samples prepared from TiO2 (A) the obtained results show a decrease in both relative density and tetragonality with both of Fe2O3 addition and sintering temperature, as a consequence we get a decrease in the relative permittivity compared with pure BTA. The Curie-Weiss law shows a linear ferroelectric property for Fe doped both BTA and BTR ceramics with a first order type of Curie phase transition. In other hand, the modified Curie-Weiss law shows a partially relaxor ferroelectric behavior for both Fe-doped BTA and BTR ceramics. The electrical resistivity evolution in term of temperature shows a semiconductor behavior with independence between applied potential and activation energy, where Fe3+ ions act as an acceptorDiplôme : Doctorat en sciences En ligne : ../theses/physique/BOU7596.pdf Format de la ressource électronique : Permalink : index.php?lvl=notice_display&id=11432 Les effets des phases du dioxyde de Titane sur les propriétés structurales et diélectriques des céramiques du type BaTiO3 + x % mole Fe2O3. [texte imprimé] / Rabah Bounouioua, Auteur ; Mohmed Tahar Benlahrache, Directeur de thèse . - 15/07/2019 . - جامعة الإخوة منتوري قسنطينة, 2019 . - 95 f. ; 30 cm.
1 copies imprimées disponibles
Langues : Français (fre)
Catégories : Français - Anglais
PhysiqueTags : sciences des matériaux:Céramique BaTiO3 (A) BaTiO3 (R) phases TiO2 phase tétragonale phase hexagonale Propriétés diélectriques TiO2 phases tetragonal phase hexagonal phase dielectrics properties أطوار TiO2 طور رباعي طور سداسي خصائص كهروعزلية Index. décimale : 530 Physique Résumé :
The objective of this investigation is to study the influence of TiO2 phases on the structural and dielectric properties of the BaTiO3 ceramics containing different amounts of Fe2O3. The pure BaTiO3 ceramics was prepared by a solid state reaction between BaCO3 and both of TiO2 phases ; anatase (A) and rutile (R), respectively. We prepared the mixtures by stoichiometric way, which were calcined at 1100 °C during 2hours. The formations of perovskites structures ABO3 were confirmed by X rays diffraction analysis. While the ceramics mixture with (1-x) BaTiO3+ x % Fe2O3 (where x = 1, 2, 5 and 7 wt %) compositions were prepared by the wet milling. Afterwards, the different pellets were fabricated by uniaxial compression and sintered at different temperatures (1300, 1350 and 1400 °C). The obtained results show an increase in the tetragonality due to the doping by Fe3+, consequencely an increase in the relative permittivity of samples prepared from TiO2(R) with both of Fe2O3 addition and sintering temperature. On the other hand, for the samples prepared from TiO2 (A) the obtained results show a decrease in both relative density and tetragonality with both of Fe2O3 addition and sintering temperature, as a consequence we get a decrease in the relative permittivity compared with pure BTA. The Curie-Weiss law shows a linear ferroelectric property for Fe doped both BTA and BTR ceramics with a first order type of Curie phase transition. In other hand, the modified Curie-Weiss law shows a partially relaxor ferroelectric behavior for both Fe-doped BTA and BTR ceramics. The electrical resistivity evolution in term of temperature shows a semiconductor behavior with independence between applied potential and activation energy, where Fe3+ ions act as an acceptorDiplôme : Doctorat en sciences En ligne : ../theses/physique/BOU7596.pdf Format de la ressource électronique : Permalink : index.php?lvl=notice_display&id=11432 Exemplaires (1)
Code-barres Cote Support Localisation Section Disponibilité BOU/7596 BOU/7596 Thèse Bibliothèque principale Thèses Disponible
Titre : « Synthèse, étude structural et caractérisations des céramiques PZT de type pérovskite Pb1-xCax [(Zr0.53, Ti0.47)0.75Sb0.25]O3 » Type de document : texte imprimé Auteurs : Doreir Benzebeiri, Auteur ; Ahmed Boutarfaia, Directeur de thèse Editeur : Constantine : Université Mentouri Constantine Année de publication : 2012 Importance : 92 f. Format : 31 cm. Note générale : Magister
2 copies imprimées disponiblesLangues : Français (fre) Catégories : Français - Anglais
ChimieTags : PZT Structure pérovskite Propriétés diélectriques Diffraction des rayons X sur poudre Frontière morphotropique de phase (F.M.P) densité Porosite Index. décimale : 540 Chimie et sciences connexes En ligne : ../theses/chimie/BEN6089.pdf Format de la ressource électronique : Permalink : index.php?lvl=notice_display&id=6062 « Synthèse, étude structural et caractérisations des céramiques PZT de type pérovskite Pb1-xCax [(Zr0.53, Ti0.47)0.75Sb0.25]O3 » [texte imprimé] / Doreir Benzebeiri, Auteur ; Ahmed Boutarfaia, Directeur de thèse . - Constantine : Université Mentouri Constantine, 2012 . - 92 f. ; 31 cm.
Magister
2 copies imprimées disponibles
Langues : Français (fre)
Catégories : Français - Anglais
ChimieTags : PZT Structure pérovskite Propriétés diélectriques Diffraction des rayons X sur poudre Frontière morphotropique de phase (F.M.P) densité Porosite Index. décimale : 540 Chimie et sciences connexes En ligne : ../theses/chimie/BEN6089.pdf Format de la ressource électronique : Permalink : index.php?lvl=notice_display&id=6062 Exemplaires (1)
Code-barres Cote Support Localisation Section Disponibilité BEN/6089 BEN/6089 Thèse Bibliothèque principale Thèses Disponible
Titre : دراسة الخصائص الفـيزيـائـية للبورسلان المحضر إنطلاقا من مواد أولية محلية Type de document : texte imprimé Auteurs : سعاد قصراني, Auteur ; عبد الحميد حرابي, Directeur de thèse Editeur : جامعة الإخوة منتوري قسنطينة Année de publication : 2017 Importance : 141 ورقة. Format : 30 سم. Note générale : 2نسخ موجودة مكتبة المركزية
Langues : Arabe (ara) Catégories : Arabe
الفيزياءTags : Porcelain Zinc oxide Titanium oxide Mechanical properties dielectrical properties Porcelaine oxyde de zinc oxyde de titane propriétés mécaniques propriétés diéléctriques البورسلان أكسيد الزنك أكسيد التيتان خصائص ميكانيكية خصائص عزلية Index. décimale : 530 الفيزياء Résumé : The aim of this work is to prepared porcelain with high mechanical and dielectric properties by
using economical native raw materials without providing ideal high-cost conditions. The basic
porcelain composition was selected consisting of 30 wt% kaolin, 45 wt% potash-feldspar and 25
wt% quartz. It was prepared by sintering the mixture at different temperatures (1140–1260 °C).
The optimum sintering conditions gave a bulk higher density (2.41 g/cm3) and excellent
mechanical properties. The three point flexural strength, Vickers micro-hardness of porcelains
were 205 MPa and 6.8 GPa, respectively. Dielectric measurements have been carried out at 1
KHz from room temperature to 200 °C. The dielectric constant, dielectric loss tangent, and
resistivity of the porcelain sample sintered at 1160 °C were 25, 0.008 and 9 x 1013 .cm,
respectively. So these values reveal that the porcelain is a good insulator. The mechanical and
dielectric properties of porcelain are improved by addition of titanium oxide and zinc oxide. The
addition of titanium oxide improved both mechanical and dielectrical properties. The optimum
sintering conditions gave a higher bulk density (2.47 g.cm−3) and excellent mechanical
properties. The three point flexural strength (3PFS), Vickers micro hardness of samples
containing 5 wt TiO2 and sintered at 1160 °C were 238 MPa, 12.3 GPa , respectively. The
dielectric constant, dielectric loss tangent of samples containing 5 wt TiO2 sintered at 1160 °C
for 2 h were: 31,0.005, respectively. These values were permitted to confirm that this is typical
insulating material. The mechanical properties of this latter may candidate it to be used in many
fields and several applications. Moreover, the addition of zinc oxide improved both mechanical
and dielectric properties. The optimum sintering conditions gave excellent mechanical
properties: The three point flexural strength, Vickers micro hardness of samples containing
5wt ZnO and sintered at 1160 °C were 242 MPa, 14.5 GPa, respectively. But it did not have a
significant impact on the dielectric properties. Besides, the maximum value of the three point
flexural strength achieved for the samples containing 5 wt TiO2 and 5 wt ZnO are nearby
that of the flexural strength of porcelain containing 5 wt% TiO2 and 30 wt % alumina (about 240
MPa). In other words, the presence of 30 wt % alumina in their product well confirm the benefic
effect of the used raw materials (saving 30 wt % alumina) on porcelain strengthening.Diplôme : Doctorat en sciences En ligne : ../theses/physique/AKAS4189.pdf Format de la ressource électronique : Permalink : index.php?lvl=notice_display&id=10685 دراسة الخصائص الفـيزيـائـية للبورسلان المحضر إنطلاقا من مواد أولية محلية [texte imprimé] / سعاد قصراني, Auteur ; عبد الحميد حرابي, Directeur de thèse . - جامعة الإخوة منتوري قسنطينة, 2017 . - 141 ورقة. ; 30 سم.
2نسخ موجودة مكتبة المركزية
Langues : Arabe (ara)
Catégories : Arabe
الفيزياءTags : Porcelain Zinc oxide Titanium oxide Mechanical properties dielectrical properties Porcelaine oxyde de zinc oxyde de titane propriétés mécaniques propriétés diéléctriques البورسلان أكسيد الزنك أكسيد التيتان خصائص ميكانيكية خصائص عزلية Index. décimale : 530 الفيزياء Résumé : The aim of this work is to prepared porcelain with high mechanical and dielectric properties by
using economical native raw materials without providing ideal high-cost conditions. The basic
porcelain composition was selected consisting of 30 wt% kaolin, 45 wt% potash-feldspar and 25
wt% quartz. It was prepared by sintering the mixture at different temperatures (1140–1260 °C).
The optimum sintering conditions gave a bulk higher density (2.41 g/cm3) and excellent
mechanical properties. The three point flexural strength, Vickers micro-hardness of porcelains
were 205 MPa and 6.8 GPa, respectively. Dielectric measurements have been carried out at 1
KHz from room temperature to 200 °C. The dielectric constant, dielectric loss tangent, and
resistivity of the porcelain sample sintered at 1160 °C were 25, 0.008 and 9 x 1013 .cm,
respectively. So these values reveal that the porcelain is a good insulator. The mechanical and
dielectric properties of porcelain are improved by addition of titanium oxide and zinc oxide. The
addition of titanium oxide improved both mechanical and dielectrical properties. The optimum
sintering conditions gave a higher bulk density (2.47 g.cm−3) and excellent mechanical
properties. The three point flexural strength (3PFS), Vickers micro hardness of samples
containing 5 wt TiO2 and sintered at 1160 °C were 238 MPa, 12.3 GPa , respectively. The
dielectric constant, dielectric loss tangent of samples containing 5 wt TiO2 sintered at 1160 °C
for 2 h were: 31,0.005, respectively. These values were permitted to confirm that this is typical
insulating material. The mechanical properties of this latter may candidate it to be used in many
fields and several applications. Moreover, the addition of zinc oxide improved both mechanical
and dielectric properties. The optimum sintering conditions gave excellent mechanical
properties: The three point flexural strength, Vickers micro hardness of samples containing
5wt ZnO and sintered at 1160 °C were 242 MPa, 14.5 GPa, respectively. But it did not have a
significant impact on the dielectric properties. Besides, the maximum value of the three point
flexural strength achieved for the samples containing 5 wt TiO2 and 5 wt ZnO are nearby
that of the flexural strength of porcelain containing 5 wt% TiO2 and 30 wt % alumina (about 240
MPa). In other words, the presence of 30 wt % alumina in their product well confirm the benefic
effect of the used raw materials (saving 30 wt % alumina) on porcelain strengthening.Diplôme : Doctorat en sciences En ligne : ../theses/physique/AKAS4189.pdf Format de la ressource électronique : Permalink : index.php?lvl=notice_display&id=10685 Exemplaires (1)
Code-barres Cote Support Localisation Section Disponibilité قصر/4189 قصر/4189 Thèse Bibliothèque principale Thèses Disponible
