0 Introduction
This standard specifies requirements for electroplated coatings of tin on fabricated metal articles to protect them from corrosion and to improve solderability.
Attention is drawn to legislative requirements that exist in many countries for tin coatings used in the food industry.
Annex C gives additional information to the users.
The purchaser shall state the information itemized in 4.1 and 4.2 except specifying the number of this standard.
1 Scope
This standard specifies requirements for electroplated tin coatings of nominally pure on fabricated metal articles. The coatings may be dull or bright as electroplated or may be flow-melted by fusion after electroplating.
This standard is not applicable to:
a) threaded components;
b) tin-coated copper wire;
c) tin coatings on sheet, strip or wire in unfabricated form, or on articles made from them;
d) tin coatings on coil springs;
e) tin coatings applied by chemical means (immersion, autocatalytic or chemical plating)
f) electroplating of steels with tensile strength greater than 1000 MPa (or of corresponding hardness), because such steels are subject to hydrogen embrittlement.
2 Normative References
The provisions of the following documents, through reference in this text, constitute the provisions of this standard. For dated reference, subsequent amendments to (excluding corrections to), or revisions of, any of these publications do not apply. However, parties to agreements based on this standard are encouraged to investigate the possibility of applying the most recent editions of the standards indicated below. For undated references, the latest edition referred to apply.
GB/T 2423.28 Basic Environmental Testing Procedures for Electric and Electronic Products; Test T: Soldering (Eqv IEC 68-2-20)
GB/T 4955 Metallic Coatings-Measurement of Coating Thickness - Coulometric Method by Anodic Dissolution (Idt ISO 2177)
GB/T 5270 Metallic Coatings on Metallic Substrates; Electrodeposited and Chemically Deposited Coatings; Review of Methods Available For Testing Adhesion (Eqv ISO 2819)
GB/T 6462 Metallic and Oxide Coatings; Measurement of Coating Thickness; Microscopical Method (Eqv ISO 1463)
GB/T 9789 Metallic and Other Non-Organic Coatings-Sulfur Dioxide Test with General Condensation of Moisture (Eqv ISO 6988)
GB/T 10125 Corrosion Tests in Artificial Atmospheres — Salt Spray Tests (Eqv ISO 9227)
GB/T 12334 Metallic and Other Inorganic Coatings--Definitions and Conventions Concerning the Measurement of Thickness (Idt ISO 2064)
Foreword i
0 Introduction
1 Scope
2 Normative References
3 Terms and Definitions
4 Information to be Supplied by the Purchaser to the Electroplater
5 Basis Material
6 Sampling
7 Classification
8 Heat Treatment of Steel
9 Requirements for Undercoats
10 Requirements for Coatings
Annex A (Informative) Determination of Coating Thickness
Annex B (Normative) Adhesion Test
Annex C (Informative) Guidance Notes
