Corrosion Testing for Metal Finishing (eBook)

Front Cover 1
Corrosion Testing for Metal Finishing 2
Copyright Page 3
Table of Contents 6
Preface 4
Membership of the Working Party 7
Other co-operating bodies 7
Acknowledgements 7
Chapter 1. Preparation for testing 8
Type of test specimen 8
Method of preparation for corrosion testing 9
The choice of corrosion test method 10
The information required 11
The nature of the test article 13
The particular finish to be tested 14
The intended end use of the article 14
Chapter 2. Quality control testing of coatings using accelerated corrosion tests 15
References 16
Chapter 3. Sampling 18
Purpose of sampling 18
The nature of product characteristics 18
Sampling for production control 19
Cumulative sum (cusum) charts for production control 20
Acceptance testing 22
References 27
Chapter 4. Methods of assessment of corrosion damage 28
Loss of protective value 28
Loss of decorative value 29
References 32
Chapter 5. Outdoor exposure testing 33
Test specimens 34
Corrosion environment 35
Test sites 35
Methods of exposure 35
Data recording 36
Test periods 37
Standard and 'control' specimens 37
Cleaning 37
Assessment, evaluation and recording of results 38
Processing of data 38
References 38
Chapter 6. Methods of testing atmospheric corrosivity 40
The CLIMAT test ('wire-in-bolt test') 40
Electrochemical methods of assessing atmospheric corrosivity 43
Zinc can method of assessing atmospheric corrosivity 44
References 46
Chapter 7. Humidity tests 48
Simple humidity tests 48
Cyclic humidity tests 49
Paint humidity tests 50
References 51
Chapter 8. Salt fog tests 52
Development of the tests 52
Test cabinets 54
Cleaning and exposure of specimens 56
Test duration 56
Test procedure 56
Evaluation and reporting of results 57
Test equipment 57
Individual test methods 57
Alternative NSS test for paints for metal surfaces 59
Salt droplet test 60
Factors affecting salt spray tests 61
References 65
Chapter 9. Tests in sulphur-bearing atmospheres 66
CRL beaker test 67
Kesternich-type test 68
AT & E test
Clarke and Leeds test 71
Industrial atmosphere test 72
Thioacetamide test 72
Correlation of sulphur gas test results with service experience 73
Types of defects produced in the tests 73
References 74
Chapter 10. Industrial atmosphere test 75
Test method 75
Factors affecting operation 78
Types of corrosion produced 80
Applicability of the test 80
Correlation with service experience 81
References 81
Chapter 11. Porosity tests 83
Test principles 83
Specific test methods 84
References 88
Chapter 12. Corrodkote test 89
Test method 89
References 91
Chapter 13. Electrolytic corrosion (EC) test 92
Principles of the test method 92
Type of corrosion produced 94
Application of the test 94
General use of the test 94
References 95
Chapter 14. Alternate-immersion tests 96
Dip-and-dry test 96
Alternate-immersion/emersion test for aircraft paints 97
References 97
Chapter 15. Bimetallic test for hard anodized aluminium 98
Test method 98
Acknowledgement 99
Chapter 16. Mortar test 100
Testing of coated metals 101
Test method 101
References 102
Chapter 17. Testing the corrosion resistance of anodic oxide coatings on aluminium 103
The Kape test (acidified sodium sulphite) 104
The sodium acetate-acetic acid test 105
The Alcoa chromic-phosphoric acid test 106
Arbitrary tests for sealing quality 106
Dye spot test 107
Admittance (or impedance) test 108
References 109
Chapter 18. Artificial weathering tests 110
Enclosed carbon arc test 111
Alternative light sources 114
Alternative weathering cycles 114
Accelerated outdoor weathering tests 115
References 116
Chapter 19. Assessment of light-fastness 117
Light-fastness of coloured anodic oxide coatings on aluminium 117
Light-fastness of paint coatings 121
References 122
Chapter 20. Anti-perspiration tests 123
Telecommunications industry test 123
Motor industry test2 124
Watch industry test 124
References 125
Index 126