| Titre : | A study of properties of ZnO thin films deposited by spray pyrolysis technique on steel |
| Auteurs : | Roumaissa Bouharra, Auteur ; Kaouthar Berima, Auteur ; Kamal Djail, Directeur de thèse |
| Type de document : | Monographie imprimée |
| Editeur : | Biskra [Algérie] : Faculté des Sciences Exactes et des Sciences de la Nature et de la Vie, Université Mohamed Khider, 2021 |
| Format : | 1 vol. (76 p.) / couv. ill. en coul / 30 cm |
| Langues: | Anglais |
| Mots-clés: | steel, Corrosion, Inhibitors, ZnO, Spray pyrolysis , Electrochemical measurements , Gravemitric study |
| Résumé : |
Corrosion is the process of deterioration or failure of a material resulting from a chemical reaction between the material and its surrounding environment. It is a phenomenon of special importance from the economic side and at the level of all human activities. Through this work, our goal was to find a way to reduce steel corrosion by using inhibitors, specifically by using layers of ZnO located using Spray pyrolysis technique and to study its effectiveness against corrosion in hydrochloric solution. We conducted this study using two different methods, mass loss study and electrochemical measurements, and we obtained results showing that using thin layers of ZnO alone was not able to protect the steel substrate from corrosion. |
| Sommaire : |
Thanking Dedication Summary List of figures List of tables Introduction.............................................................................................. 01 Part I: bibliographic study Chapter I: corrosion of metals and inhibitors I Steels ................................................................................................... 05 I.1 History of steels ..............05 I.2 Definition of steel ................................................................................................05 I.3 Classification of steels ................................06 I.3.1 Ordinary steels or carbon steels ..................................................06 I.3.2 Heat treatment steels..................................................08 I.3.3 Tool steels ........................................................................08 I.3.4 Stainless steels................................................................08 I.3.4.1 Martensitic .....................................................09 I.3.4.2 Ferritic ........................................................................09 I.3.4.3 Austentitic......................................................................09 I.3.4.4 Precipitation-hard enable stainless steels ..........................................................................09 II Corrosion ........................................................................................... 10 II.1 History........................................................................10 II.2 Definition..................................................................11 II.3 Classification..................................................................11 II.4 Forms of corrosion........................................................................................................12 II.4.1 General corrosion .........................................................................................................12 II.4.2 Galvanic corrosion .......................................................................13 II.4.3 Crevice corrosion or deposit corrosion..........................................................................13 II.4.4 Pittig corrosion or localized corrosion ...............................................................14 II.4.5 Intergranular corrosion (IGC)..................................................................14 II.4.6 Selective leaching corrosion ..........................................................15 II.4.7 Erosion corrosion .............................................................................15 II.4.8 Stress corrosion ..................................................................16 II.4.9 Corrosion fatigue.................................................................................17 II.4.10 Fretting corrosion ........................................................................17 II.4.11 Cavitations corrosion..................................................................................................18 II.5 Factors influencing corrosion.......................................................................................19 II.6 Corrosion assessment methods.....................................................................................19 II.6.1 Gravimetry...............................................................................................19 II.6.2 Electrochemical methods.............................................................................20 II.6.3 Stationary method: polarization curves ..................................................20 II.6.4 Transient method: electrochemical impedance spectroscopy.........................................22 III Corrosion inhibitor .................................................................. 23 III.1 Definition of inhibitor.......................................................23 III.2 Classification of Inhibitors...................................................................24 III.2.1 Based on electrode process...................................................................24 III.2.1.1 Anodic inhibitors ...................................................................24 III.2.1.2 Cathodic inhibitors........................................................................................25 III.2.1.3 Mixed inhibitors ...................................................................26 III.2.2 Based on environment.................................................................................26 III.2.2.1 Acidic environment inhibitors.......................................................................26 III.2.2.1.1 Inorganic inhibitors...........................................................26 III.2.2.1.2 Organic inhibitors .................................................................................26 III.2.2.1.3 Alkaline inhibitors.................................................................................27 III.2.2.1.4 Neutral inhibitors ..................................................................................27 III.2.3 Based on mode of protection.........................................................27 III.2.3.1 Chemical passivators .........................................................27 III.2.3.2 Adsorption inhibitors ....................................................................................27 III.2.3.3 Film forming inhibitors.....................................................28 III.2.4 Vapor phase inhibitors ...............................................................................................28 Chapter II: ZnO thin films deposition and characterization I Transparent and conductive oxides30 II Zinc oxide.................................................................... 30 II.1 Definition .............................................................31 II.2 The ZnO selection..............................................................................................31 II.3 Properties of zinc oxide ZnO ...........................................................32 II.3.1 Crystallographic properties .....................................................................32 II.3.2 Electrical properties .................................................................34 II.3.3 Optical Properties ......................................................................34 II.3.4 Chemical Properties.........................................................................36 II.3.5 Catalytic properties...........................................................................36 II.4 Bienfaits of ZnO .............................................................................36 III Thin films ........................................................................ 37 III.1 General concept of thin films.............................................................37 III.2 Principle of thin film deposition ..........................................................37 III.3 Selection of a thin film deposition technique ......................................39 IV Spray pyrolysis .......................................................................... 40 IV.1 Definition.............................................................................40 IV.2 Principle of the technique ................................................................................40 IV.3 Installation description .........................................................................41 IV.4 Spray deposition process......................................................................42 IV.4.1 Aerosol generation ............................................................42 IV.4.2 Transport of the aerosol......................................................43 IV.4.3 Chemical decomposition ..................................................................44 IV.5 Advantages of spray pyrolysis technique ........................................................45 IV.6 Influence of the some main Spray pyrolysis technique parameters on the quality of the deposited films ....................................................46 IV.6.1 Influence of the Temperature...........................................................................46 IV.6.2 Influence of precursor solution ........................................................................46 V Methods of thin film characterization ............................................... 47 V.1 X-ray Diffraction (XRD)……............................................................................47 V.2 Scanning Electron Microscope (SEM)..............................................................50 V.3 Optical microscope ....................................................................51 V.4 Energy Dispersive X-Ray Analysis (EDX)........................................................52Part II: Experimental study Chapter III: Methods and Materials I Experimental Procedure.......................................................... 56 I.1 Substrate preparation ..........................................................................56 I.1.1 Cutting ......................................................................................57 I.1.2 Polishing .....................................................................................57 I.2 The preparation of the solution of acetate of zinc ................................58 I.3 Elaboration of thin ZnO films ...........................................60 I.3.1 Thin film deposition parameters ........................................60 I.3.2 Layers deposition.............................................................................. II Experimental characterization .................................................................... 62 II.1 Optical microscope observation……………………………………………..……. .......62 II.2 Scanning Electron Microscope (SEM)…………………….…………….………..........63 II.3 Energy Dispersive X-Ray Analysis (EDX)….……………………………...……. ........63 II.4 X-ray diffraction studies (XRD)………………………………………..………… ........64 III Taste of corrosion .................................................... … ... 65 III.1 Gravimetric study ....................................................................................65 III.1.1 Preparation of corrosive media…….…………………….……….………....................65 III.1.2 Testing techniques……………………………………………………..…… ................66 III.2 Electrochemical measurements67 Chapter IV:Results and discussions I Experimental characterization............................................ 69 I.1 Optical microscope observations ...................................................................................69 I.2 Scanning Electron Microscope (SEM) Characterization.....................................70 I.3 Energy Dispersive X-Ray Analysis (EDX) .............................................................71 I.4 X-ray diffraction studies (XRD) ......................................................................72 IITaste of corrosion.................................................................... 73 II.1 Gravemitric study II.2 Electrochemical measurements ........................................ 75 General Conclusion............................................................. 77 BIBILIOGRAPIC REFERENCE ABSTRACT |
| Type de document : | Mémoire master |
Disponibilité (1)
| Cote | Support | Localisation | Statut |
|---|---|---|---|
| MCH/484 | Mémoire master | bibliothèque sciences exactes | Consultable |
