AS 1627.6-1994

1 - AS 1627.6-1994 METAL FINISHING - PREPARATION AND PRETREATMENT OF SURFACES - CHEMICAL CONVERSION TREATMENT OF METALS
4 - PREFACE
5 - CONTENTS
6 - FOREWORD
7 - SECTION 1 SCOPE AND GENERAL
7 - 1.1 SCOPE
7 - 1.2 REFERENCED DOCUMENTS
8 - 1.3 DEFINITIONS
8 - 1.3.1 Chromate coatings, non-rinsed
8 - 1.3.2 Chromate coatings, rinsed
8 - 1.3.3 Organic coating
8 - 1.3.4 Phosphating process (accelerated)
8 - 1.3.5 Phosphating process (unaccelerated)
8 - 1.3.6 Sealing
8 - 1.3.7 Smut
8 - 1.3.8 Staining
8 - 1.4 SAFETY PRECAUTIONS
8 - 1.4.1 General
8 - 1.4.2 Health hazards
8 - 1.4.3 Handling solutions
8 - 1.4.4 Protective clothing
8 - 1.4.5 Ventilation
9 - 1.4.6 Respiratory protection
9 - 1.4.7 Safety signs
9 - 1.4.8 Washing facilities
9 - 1.5 DISPOSAL OF WASTE SOLUTIONS
10 - SECTION 2 PHOSPHATE CONVERSION TREATMENT
10 - 2.1 SCOPE OF SECTION
10 - 2.2 COATING CLASSIFICATION
10 - 2.2.1 Coatings for iron and steel
10 - 2.2.2 Coatings for non-ferrous metals
10 - 2.3 REQUIREMENTS FOR PHOSPHATE COATINGS
10 - 2.3.1 General requirements
11 - 2.3.2 Coating mass
11 - 2.3.3 Freedom from corrosive residues
11 - 2.3.4 Resistance to corrosion
11 - 2.4 METHODS OF APPLICATION
11 - 2.4.1 General
12 - 2.4.2 Surface preparation
12 - 2.4.3 Phosphate treatment
12 - 2.4.4 Rinsing
13 - 2.4.5 Staining
13 - 2.4.6 Drying
13 - 2.4.7 Treatment of creviced components
13 - 2.4.8 Treatment of composite articles
13 - 2.4.9 Treatment of high tensile steels
14 - 2.4.10 Sealing
15 - SECTION 3 CHROMATE CONVERSION TREATMENT OF ALUMINIUM AND ALUMINIUM ALLOYS
15 - 3.1 SCOPE OF SECTION
15 - 3.2 COATING CLASSIFICATION
15 - 3.3 REQUIREMENTS FOR CHROMATE COATINGS
15 - 3.3.1 General requirements
16 - 3.3.2 Test specimens and sampling
16 - 3.3.3 Coating mass
16 - 3.3.4 Adhesion
16 - 3.3.5 Corrosion resistance
16 - 3.3.6 Coating identification
17 - 3.4 METHODS OF APPLICATION
17 - 3.4.1 Surface preparation
17 - 3.4.2 Method of application of chromate coatings
17 - 3.4.3 Rinsing and drying
18 - APPENDIX A - PURCHASING GUIDELINES
18 - A1 GENERAL
18 - A2 INFORMATION TO BE SUPPLIED BY THE PURCHASER
19 - APPENDIX B - TEST METHODS FOR THE DETERMINATION OF PHOSPHATE COATING MASS
19 - B1 GENERAL
19 - B2 PRINCIPLE
19 - B3 TEST SPECIMENS
19 - B4 DETERMINATION OF COATING MASS ON STEEL USING THE HYDROCHLORIC ACID METHOD
19 - B4.1 Reagent
19 - B4.2 Procedure
20 - B4.3 Calculation of coating mass
20 - B5 DETERMINATION OF COATING MASS ON STEEL USING THE CHROMIC ACID METHOD
20 - B5.1 Reagent
20 - B5.2 Procedure
21 - B5.3 Calculation of coating mass
21 - B6 DETERMINATION OF COATING MASS OF IRREGULAR-SHAPED OBJECTS BY DETERMINING THE PHOSPHATE CONTENT (APPLICABLE TO CLASS B AND
21 - B6.1 Reagents
21 - B6.2 Procedure
21 - B6.3 Calculation
21 - B7 TEST REPORT
23 - APPENDIX C - TEST METHOD FOR DETERMINING THE FREEDOM OF PHOSPHATE COATINGS FROM CORROSIVE RESIDUES
23 - C1 GENERAL
23 - C2 PRINCIPLE
23 - C3 PROCEDURE
23 - C4 TEST REPORT
24 - APPENDIX D - DETERMINATION OF CORROSION RESISTANCE OF PHOSPHATE COATINGS
24 - D1 DETERMINATION OF CORROSION RESISTANCE OF PHOSPHATE COATED FERROUS METALS WHICH HAVE NOT BEEN AFTER- TREATED OR ORGANICALLY COATED
24 - D1.1 Principle
24 - D1.2 Procedure
24 - D2 DETERMINATION OF CORROSION RESISTANCE OF PHOSPHATE CONVERSION COATINGS WHICH HAVE BEEN AFTER- TREATED WITH CORROSION- PREVENTINGOILS
24 - D2.1 Principle
24 - D2.2 Procedure
25 - D2.3 Neutral salt spray test
25 - D3 TEST REPORT
26 - APPENDIX E - GUIDANCE ON THE HEAT TREATMENT OF STEEL
26 - E1 STRESS RELIEF BEFORE PHOSPHATING
26 - E1.1 General
26 - E1.2 Severely cold worked steel parts
26 - E1.3 Parts made from steels of tensile strength in the range 1000 MPa to 1400 MPa
26 - E1.4 Parts made from steels of tensile strength over 1400 MPa
27 - E2 HYDROGEN EMBRITTLEMENT RELIEF AFTER PHOSPHATING
27 - E2.1 Severely cold worked steels
27 - E2.2 Surface-hardened steels
28 - APPENDIX F - DETERMINATION OF CHROMATE COATING MASS ON ALUMINIUM AND ITS ALLOYS
28 - F1 SCOPE
28 - F2 TEST SPECIMENS
28 - F3 DETERMINATON OF MASS OF FRESH CHROMATE COATINGS
28 - F3.1 Reagent
28 - F3.2 Procedure
28 - F4 DETERMINATION OF MASS OF AGED CHROMATE COATINGS
28 - F4.1 Reagent
28 - F4.2 Procedure
29 - F5 EXPRESSION OF RESULTS
29 - F5.1 Calculation
29 - F5.2 Precision
29 - F6 TEST REPORT
30 - APPENDIX G - QUALITATIVE TESTING OF THE LAYER COMPOSITION OF CHROMATE COATINGS
30 - G1 SCOPE
30 - G2 REAGENTS
30 - G3 DETERMINATION OF THE PRESENCE OF CHROMIUM
31 - G4 DETERMINATION OF THE PRESENCE OF PHOSPHATE
31 - G5 DETERMINATION OF THE PRESENCE OF ZINC
32 - APPENDIX H - CHROMATE TREATMENT SEQUENCE OPTIONS
32 - H1 TREATMENT STAGES

Specifies requirements and procedures for the chemical conversion treatment of metals. This Standard includes phosphate conversion of ferrous and non-ferrous metals, and chromate conversion of aluminium alloys. Appendices give test methods and processing information.

This Standard specifies requirements and procedures for the chemical conversion treatment of metals prior to the application of a suitable organic protective coating and includes the following processes:(a) Phosphate conversion of ferrous and non-ferrous metals.(b) Chromate conversion of aluminium and aluminium alloys.NOTES:1 This Standard does not include requirements for conversion coatings applied to electroplated work.2 Advice and recommendations on information to be supplied by the purchaser at the time of enquiry or order are contained in Appendix A.

Under Revision see DR 02425 First published as AS CK9.6-1968.Revised and redesignated AS 1627.6-1977.Second edition 1994. First published as AS CK9.6-1968. Revised and redesignated AS 1627.6-1977. Second edition 1994.