COMPARISON STUDY OF CORROSION MEASUREMENT TECHNIQUE FADLI BIN

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1 i COMPARISON STUDY OF CORROSION MEASUREMENT TECHNIQUE FADLI BIN This thesis is submitted as a partial fulfilment of the requirements for the award of the Bachelor of Mechanical Engineering Faculty of Mechanical Engineering UNIVERSITI MALAYSIA PAHANG JUNE 2013

2 UNIVERSITI MALAYSIA PAHANG BORANG PENGESAHAN STATUS TESIS JUDUL: Saya A STUDY OF DYNAMIC CHARATERISTICS FOR CRACK IDENTIFICATION SESI PENGAJIAN: 2009/2013 FADLI BIN MISLAN@MISHADI ( ) (HURUF BESAR) mengaku membenarkan tesis (Sarjana Muda/Sarjana /Doktor Falsafah)* ini disimpan di Perpustakaan dengan syarat-syarat kegunaan seperti berikut: 1. Tesis adalah hakmilik Universiti Malaysia Pahang (UMP). 2. Perpustakaan dibenarkan membuat salinan untuk tujuan pengajian sahaja. 3. Perpustakaan dibenarkan membuat salinan tesis ini sebagai bahan pertukaran antara institusi pengajian tinggi. 4. **Sila tandakan ( ) SULIT TERHAD (Mengandungi maklumat yang berdarjah keselamatan atau kepentingan Malaysia seperti yang termaktub di dalam AKTA RAHSIA RASMI 1972) (Mengandungi maklumat TERHAD yang telah ditentukan oleh organisasi/badan di mana penyelidikan dijalankan) TIDAK TERHAD Disahkan oleh: (TANDATANGAN PENULIS) (TANDATANGAN PENYELIA) Alamat Tetap: LOT 4715,JLN HJ SUBARI,KG BKT KERAYONG, KAPAR SELANGOR. DR YULI PANCAASMARA ( Nama Penyelia ) Tarikh: Tarikh: : CATATAN: * Potong yang tidak berkenaan. ** Jika tesis ini SULIT atau TERHAD, sila lampirkan surat daripada pihak berkuasa/organisasi berkenaan dengan menyatakan sekali tempoh tesis ini perlu dikelaskan sebagai atau TERHAD. Tesis dimaksudkan sebagai tesis bagi Ijazah doktor Falsafah dan Sarjana secara Penyelidikan, atau disertasi bagi pengajian secara kerja kursus dan penyelidikan, atau Laporan Projek Sarjana Muda (PSM).

3 VIII TABLE OF CONTENTS Pages EXAMINER DECLARATION SUPERVISOR S DECLARATION STUDENT S DECLARATION ACKNOWLEDGEMENTS ABSTRACT ABSTRAK TABLE OF CONTENTS LIST OF TABLES LIST OF FIGURES LIST OF SYMBOLS LIST OF ABREVIATIONS ii iii iv vi vi vii viii xii xiii xv xvi CHAPTER 1 INTRODUCTION 1.1 Study background Problem Statement Objectives of Study Scopes of Study 2

4 IX CHAPTER 2 LITERATURE REVIEW 2.1 Introduction Methods in measuring corrosion rate Linear Polarization Resistance Uncertainties in corrosion measurement using Electrochemical technique Linear Polarization Error Tafel Slope Uncertainties Polarization Limitation Effect of Scan Rate Charger Transfer Reaction Effect on Tafel Plot 13 CHAPTER 3 METHODOLOGY 3.1 Introduction Flow chart of work progress Experiment Procedure Non-Electrochemical (Weight Loss) Electrode Specimen Preparation Cell Solution 20

5 X 3.4 Corrosion rate measurement Weight Loss Tafel Method Linear Polarization Resistance Test Procedure Calculating Corrosion Rtae Value,Rp and Error 25 CHAPTER 4 RESULTS AND DISCUSSIONS 4.1 Introduction Result Weight Loss Method Tafel Method Linear Polarization Resistance Discussion 40 CHAPTER 5 CONCLUSIONS AND RECOMMENDATIONS 5.1 Introduction Conclusion Recommendations 42

6 XI REFERENCES 43 APPENDICES A Gantt chart of FYP 2 45 B Polarization Behaviour of a metal (M) in Acid solution 46

7 XII LIST OF TABLES Table No. Title Page 3.1 Carbon Steel X52 chemical composition Parameter of potensiostat Result for weight loss Parameter results for constant potential voltage and different scan rate Results of Rp and CR for constant potential voltage and different scan rate. 4.4 Result of errors for constant potential different(eintial:-0.5v, Efinal:0.5) and different scan rate. 4.5 Result of tafel parameter value for different potential and constant scan rate 15mV/s Result of Rp and CR value(different potential,constant scan rate) Error of Tafel s parameter(different potential,constant scan rate) Parameter and error value(same potential different,different scan rate) Result of LPR parameter value and error (different potential, constant scan rate 15mV/s 39

8 XIII LIST OF FIGURES Figure No. Title Page 2.1 Potential versus Current Density Effect of Tafel slope assumptions (B) on corrosion rate An ambiguous of Icorr Effect of scan rate on Potential and Current density An ideal Tafelplot The shift in the curve α as the potential is made more positive Effects of assumption in assuming B values Flow Chart of Progress Schematic of the experimental test cell and the electrodes configurations The Tafel graph of scan rate 15mV/s The tafel graph of scan rate 20mV/s The tafel graph of scan rate 25mV/s The combination of tafel graph of scan rate 15,20 and 25mV/s Combining Tafel Graph(Different potential,constant scan rate) LPR graph for scan rate 15mV/s LPR graph for scan rate 20mV/s LPR graph for scan rate 25mV/s 36

9 XIV 4.9 Graph of same potential different and different scan rate LPR graph for constantscan rate and different potential 38

10 XV LIST OF SYMBOLS % Percentage C Degree Celsius cm g l Centimeter Gram Liter µ Micro m mm mm/y Ba/ Bc C CR E Meter Millimeter Milimeters per year Tafel slope(anodic and cathodic), mv/decade Capacitance, F Corrosion rate Potential, V E Initial Potential Ef Ecorr Final Potential Corrosion Potential,mV Icorr Corrosion Current Density, µa/cm 2 M R Rp Molecular weight, g/mol Resistance, ohms Polarization Resistance T Temperature, C

11 XVI LIST OF ABBREVIATIONS A C Ca Cl Cr Cu D e - H HCl H2O K Na NaCl Ni O2 OH - P S Si T W Zn Area Carbon Calcium Chlorine Chromium Copper Density Electron Hydrogen Hydrochloric Acid Hydrogen Oxide (Water) Constant for corrosion rate Sodium Sodium Chloride Nickel Oxygen gas Hydroxyl Phosphorus Sulphur Silicon Time of exposure mass Zinc