ISO 3160-2-2015 pdf free.Watch-cases and accessories – Gold alloy coverings – Part 2: Determination of fineness, thickness, corrosion resistance and adhesion.
This part of Iso 3160 specifies methods to determine fineness, thickness, corrosion resistance and adhesion for gold alloy coverings on watch-cases and accessories, including bracelets when they are permanently attached to the case.
The tests apply only to significant surfaces.
This part of ISO 3160 applies to all gold alloy coverings specified in ISO 3160-1.
2 Normative references
The Following documents, in whole or in part, are normatively referenced in this document and are indispensable for its application. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.
Iso 1463, Metallic and oxide coatings — Measurement of coating thickness — Microscopical method
Iso 2177, Metallic coatings — Measurement of coating thickness — C’oulometric method by anodic dissolution
ISO 3 160-1. Watch-cases and accessories — Gold alloy coverings — Part 1: General requirements
ISO 3497, Metallic coatings — Measurement of coating thickness — X-ray spectrometric methods
ISO 3543, Metallic and non-metallic coatings — Measurement of thickness — Beta backscatter in et hod ISO 3868, Metallic and other non-organic coatings — Measurement of coating thicknesses — Fizeau multiple-beam interferometry method
ISO 4538, Metallic coatings — Thioacetamide corrosion test (TAA test)
ISO 9220, Metallic coatings — Measurement of coating thickness — Scanning electron microscope method
ISO 9227, Corrosion tests in artificial atmospheres — Salt spray tests
ISO 1 1426,jewellery — Determination of gold in gold jewellery alloys — Cupellation method (fire assay)
ISO 12687, Metallic coatings — Porosity tests — Humid sulfur (flowers of sulfur) test
ISO 14647, Metallic coatings — Determination of porosity in gold coatings on metal substrates — Nitric acid vapour test
ISO 27874, Metallic and other inorganic coatings — Electrodeposited gold and gold alloy coatings for electrical, electronic and engineering purposes — Specification and test methods
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
4 General
In the context of this part of ISO 3160, the term corrosion includes tarnishing and oxidation, as well as surface penetration and the effects of the penetration of corrosive agents into porosity and microdiscontinuities of the protection.
It is generally required that, except where specified to the contrary, gold-alloy-covered surfaces should not have suffered any damage after each of the proposed tests. In practice, however, this condition is never strictly fulfilled and certain minor changes are observed, especially at the edges of the gold- covered parts. Consequently, interpretation of the results requires a certain amount of common sense and, if necessary. agreement between the supplier and customer. The presence of such almost inevitable faults makes it impossible to sell the tested item as new. In this respect, the tests are therefore to be considered to be destructive.
The test methods apply to all gold alloy coverings specified in ISO 3160-1.
5 Determination of gold fineness
5.1 General
lithe fineness is measured on a gold alloy covering which is separated trom the base metal, the method used to separate the gold alloy covering from the base metal shall not affect the fineness of the gold covering to a significant extent.
For multilayer coverings, the covering content measured is the mean content, which shall be a minimum of 585 parts per thousand, in accordance with ISO 3160-1.
The method of separation of the sample is specified in Annex A.
5.2 Methods of gold fineness determination
Any of the following methods shall be used for the determination ol coiitenLs:
a) chemical analysis by reduction in an aqueous solution of, for example, sulfur dioxide or any other suitable reducing agent;
b) analysis by
1) cupellation (fire test) as specified in ISO 11426,
2) Energy Dispersive Spectroscopy on Scanning Electron Microscopy (SEM/ EDS),
3) atomic absorption spectrometry,
4) spectrophotometry.ISO 3160-2 pdf download.