GB/T 19351-2003 (English Version) Metallic coatings-Determination of porosity in gold coatings on metal substrates-Nitric acid vapour test

Standard No.: GB/T 19351-2003
Language: Chinese, Available in English version
Release Date: 2003
Published By: General Administration of Quality Supervision, Inspection and Quarantine of the People‘s Republic of China
Latest: GB/T 19351-2003

Scope: This standard specifies the equipment and method for determining the porosity of gold coatings, especially electrodeposited layers and gold-clad layers on electrical contacts, by the nitric acid vapor method. This method is intended to be used to explain whether the porosity is less than or greater than some values proposed by users based on experience and accepted by specific application objects. This standard is applicable to the gold-inlaid layer or gold-clad layer with a gold content of ≥75%, the electrodeposited gold layer with a gold content of ≥95%, or the copper, nickel and their alloy undercoatings usually used in electrical contacts. The nitric acid vapor test is too strict and is not suitable for gold coatings with a thickness of <0.6uμm; nor is it suitable for coatings that are more active than gold or platinum, for example, palladium and its alloys or palladium and its alloys with gold flash plating. See GB/T 17720 and literature for several other porosity test methods (for example, references [1] and [2]).

GB/T 19351-2003 history

2003 GB/T 19351-2003 Metallic coatings-Determination of porosity in gold coatings on metal substrates-Nitric acid vapour test