Corrosion Monitoring in Nuclear Systems: Research and Applications: (EFC 56)

Copyright
......Page 3
Most important abbreviations......Page 10
Preface......Page 7
Table of Contents
......Page 5
1.3 Probes for corrosion monitoring......Page 11
1.4 Accuracy of electrochemical methods......Page 13
1.5 Epilogue and answers to the questions......Page 14
2.1.1 Electrochemical techniques......Page 15
2.1.2 Non-electrochemical techniques......Page 16
2.2.1 Corrosion potential......Page 17
2.2.2 Tafel extrapolation......Page 20
2.2.3 Linear polarisation resistance......Page 21
2.2.4 Electrochemical impedance spectroscopy......Page 23
2.2.5 Harmonic analysis......Page 28
2.2.6 Intermodulation distortion technique......Page 32
2.3 Conclusions......Page 35
References......Page 38
3.1 Introduction......Page 42
3.2 Repassivation with the Scratch Technique......Page 44
3.3.2 Example 2......Page 47
3.3.3 Example 3......Page 48
3.4 Electrochemical Noise Generator Based on Repassivation Kinetics......Page 49
Conclusions......Page 53
References......Page 55
4.1 Introduction......Page 56
4.2.2 Experimental Procedure......Page 57
4.2.2.1 Electrochemical Noise Measurements......Page 59
4.2.2.2 Direct Current Potential Drop Measurements......Page 61
4.3 Results and Discussion......Page 62
Acknowledgement......Page 71
References......Page 72
5.1 Introduction......Page 73
5.2.1 Materials......Page 74
5.2.3 Electrochemical Noise Instrumentation......Page 75
5.3 Results......Page 76
References......Page 89
6.1 Introduction......Page 91
6.2 Experimental......Page 92
6.3.1 Microscopic Analysis......Page 93
6.3.2 Electrochemical Noise Analysis......Page 95
References......Page 104
7.1 Introduction......Page 106
7.2 Experimental......Page 107
7.3.2 Impedance Measurements......Page 109
7.3.2.1 Impedance of Oxide Layer......Page 112
7.3.2.2 Polarisation Resistance and Double Layer Capacitance......Page 118
7.3.2.3 Diffusion Impedance......Page 123
Conclusions......Page 125
Acknowledgement......Page 127
References......Page 128
8.1 Introduction......Page 130
8.2 Experimental Set-up......Page 131
8.3.1 Potential and Current Transient Response to SCC Initiation and Propagation......Page 132
8.3.2 Interpretation of R614 Results......Page 133
8.3.3 Estimate of Charge Transferred during Localised Corrosion Events for R614......Page 136
8.3.4 Additional Tests Interrupted after First Large Transient......Page 137
8.3.5 Analysis of Charge Associated with Transients for R628......Page 140
8.3.7 Interrupted Test Completion for R628......Page 142
8.3.8 Analysis of Charge Sizes for Specimen R628......Page 143
8.4.1 AE Results for R614......Page 145
8.4.3 Interpretation of AE Results for R614......Page 147
8.4.4 AE Results for Specimen R628......Page 148
8.4.5 Analysis of Acoustic Emission Results for R628......Page 149
Conclusions......Page 150
Acknowledgements......Page 151
References......Page 152
9.2.1 Materials and Solutions......Page 153
9.2.2 Reference Electrode......Page 154
9.3.1 Corrosion Monitoring......Page 155
9.3.3 Time Evolution of the Transfer Conductance at 90°C......Page 158
9.3.4 Time Evolution of the Transfer Conductance at 50°C......Page 159
9.3.5 Corrosion Products at 150°C......Page 160
9.3.6 Corrosion Products at 90°C......Page 161
9.4 Discussion......Page 163
Conclusions......Page 165
References......Page 166
10.2 Requirements for In-Line Water Chemistry Sensors......Page 168
10.3 High-Temperature Water Chemistry Sensors......Page 172
10.4 Experience with High-Temperature Water Chemistry Sensors in Operating Plants......Page 176
References......Page 178
11.1 Introduction......Page 181
11.2 Description of Test Loops......Page 182
11.3 On-Line Crack Growth Rate Measurements......Page 183
11.4 Crack Initiation Measurements......Page 185
11.5 Irradiation Creep and Stress Relaxation Measurements......Page 189
11.6 In-Core ECP Measurements......Page 191
11.7 In-Core Conductivity Measurements......Page 196
11.8.1 On-Line Potential Drop Corrosion Monitor......Page 199
11.8.2 Electrochemical Impedance Spectroscopy......Page 201
References......Page 202
12.2.1 ECP Monitoring in BWR......Page 204
12.2.2 Crack Growth Rate Measurements......Page 207
12.2.3 Electrochemical Noise Monitoring during a Decontamination Process......Page 209
12.2.4 ECP Monitoring in PWR Secondary Water......Page 213
12.2.6 Pipe-Thinning Monitor......Page 215
Conclusions......Page 218
References......Page 220
13.1 Introduction......Page 221
13.2 Previous Experience......Page 222
13.2.1 Measurements at the Ringhals PWRs in Sweden......Page 223
13.2.2 Comparison between In-Pipe and Side-Stream Autoclave Measurements......Page 224
13.3 The New Electrode Arrangement......Page 228
References......Page 229
14.1 Introduction......Page 231
14.2 Experimental Techniques......Page 232
14.3.2 Redox and Corrosion Potentials......Page 238
14.3.3 Transport of Particulate Iron......Page 241
14.3.5 Iron Redox States at Different Hydrazine Concentrations......Page 242
14.3.7 Comparison of Measured and Calculated Redox Potentials......Page 244
References......Page 247
15.1 Introduction......Page 249
15.2.1 Control of Corrosive Conditions......Page 250
15.2.3 In-situ Measurements......Page 251
15.3.2 In-situ Corrosive Condition Measurements......Page 252
15.3.3 Anodic Polarisation Current Measurements......Page 253
15.4.2 Effects of Hydrogen Peroxide and Oxygen on ECP and FDCI......Page 254
15.4.4 Equivalent Circuit Analysis......Page 256
15.5.1 Sensor Array......Page 258
15.5.2 Reference Electrode......Page 259
15.5.3 Alternative Data Processing......Page 260
Acknowledgements......Page 262
References......Page 263
Index
......Page 265