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Publié par | universitat_bayreuth |
Publié le | 01 janvier 2009 |
Nombre de lectures | 74 |
Langue | English |
Poids de l'ouvrage | 4 Mo |
Extrait
Sintering kinetics and properties of highly pure
lead zirconate titanate ceramics
Von der Fakultät für Biologie, Chemie und Geowissenschaften der
Universität Bayreuth
Zur Erlangung der Würde eines Doktors der Naturwissenschaften
– Dr. rer. nat. –
Genehmigte Dissertation
Vorgelegt von
Xianliang Huang (黄贤良)
aus AnQing, China
Würzburg 2009
Erklärung
Hiermit erkläre ich ehrenwörtlich, daß ich die Dissertation „Sintering kinetics and
properties of highly pure lead zirconate titanate ceramics“ selbständig angefertigt und
keine anderen als die von mir angegebenen Quellen und Hilfsmittel benutzt habe.
Ich erkläre außerdem, daß diese Dissertation weder in gleicher oder anderer Form bereits
in einem anderen Prüfungsverfahren vorgelegen hat.
Ich habe früher außer den mit dem Zulassungsgesuch urkundlich vorgelegten Graden
keine weiteren akademischen Grade erworben oder zu erwerben versucht.
Würzburg, den 27. 07. 2009
_________________________
Xianliang Huang
To those who have supported me through this endeavor
In memory of a dear friend Patrick FiedlerTable of Contents I
Table of Contents
Abstract............................................................................................................................................................i
Zusammenfassung........iii
Chapter 1 Introduction...1
1.1 Piezoelectricity.............................................................................................................................1
1.2 Ferroelectricity2
1.3 Lead zirconate titanate................................................................................................................6
1.3.1 Phase diagram and morphotropic phase boundary (MPB).........................................6
1.3.2 Synthesis and reaction sequences of PZT.......................................................................7
1.3.3 Studies on sintering...........................................................................................................8
1.3.4 Major variables affecting the properties of PZT ceramics..........................................11
1.3.5 Dopant effects on PZT ceramics.....................................................................................14
1.4 Purpose of present research.....................................................................................................17
Chapter 2 Experimental procedure............................................................................................................19
2.1 Characterizing Methods19
2.1.1 Powder characterization.................................................................................................19
2.1.2 Characterization of sintered PZT ceramics..................................................................20
2.2 Specimen Preparation...............................................................................................................22
2.2.1 Raw materials...................................................................................................................22
2.2.2 Synthesis of PZT powders..............................................................................................22
2.2.3 Green sample preparation and sintering......................................................................25
2.3 In situ measurement of sintering behavior............................................................................25
2.3.1 General procedure...........................................................................................................25
2.3.2 Sintering in closed crucible.............................................................................................26
Chapter 3 Data evaluation..........................................................................................................................28
3.1 Rietveld refinement...................................................................................................................28
3.2 Image analysis............................................................................................................................29
3.2.1 Grain size measurement..................................................................................................29
3.2.2 Homogeneity evaluation................................................................................................29
3.3 Sintering behavior of PZT ceramics in TOMMI....................................................................30
3.3.1 Temperature calibration30
II Table of Content
3.3.2 Correction of thermal expansion...................................................................................30
3.3.3 Calculation of sintering temperatures...........................................................................31
3.3.4 Kinetic field and activation energy for sintering of PZT............................................31
Chapter 4 Lead zirconate titanate ceramics from different raw materials and with lead
nonstoichiometry.........................................................................................................................................33
4.1 Introduction.33
4.2 Comparison of PZT ceramics prepared from industrial‐used and highly pure raw
materials.....................33
4.2.1 Differential Thermal Analysis........................................................................................33
4.2.2 X‐ray Diffraction Analysis..............................................................................