CEN/TC 262/SC 1 - Coatings

This document specifies a destructive method for the measurement of the local thickness of metallic and other inorganic coatings by examination of cross-sections with a scanning electron microscope (SEM). The method is applicable for thicknesses up to several millimetres, but for such thick coatings it is usually more practical to use a light microscope (see ISO 1463). The lower thickness limit depends on the achieved measurement uncertainty (see Clause 10).
NOTE       The method can also be used for organic layers when they are neither damaged by the preparation of the cross-section nor by the electron beam during imaging.

This document specifies four electrographic tests for assessing the porosity of electrodeposited gold and gold alloy coatings for engineering, and decorative and protective purposes.

This second edition cancels and replaces the first edition (i. e. ISO 2361:1972). Specifies the method of using coating thickness instruments of the magnetic type ror non-destructive measurements of the thickness. The method may nkot be applicable to autocatalytic (electroless) nickel coatings. For the purpose of this Standasd, two types of nickel coating are disringuished: coatings on magnetic substrates and on non-magnetic substrates.

Specifies the test solution, the apparatus and the procedure for a saline droplets corrosion test. Is suitable for detecting defests and discontinuities. It is also suitable for chemical or electrochemical conversion coatings. Is not suitable for testing coatings intended for the more severe types of service. The type and number of test specimens, the exposure periods to be used for a particular product and the interpretaiton of results are not specified.

Gives guidance on methods of corrosion testing of protective metallic, conversion and other non-organic coatings, with or without additive protection, in heated und unheated storage rooms in all microclimates with or without control of climatic parameters. Specimens and articles may be tested separately or in bilk, and with protective wrappings.

Specifies the reagent, the apparatus and the procedure for assessment of the quality of metallic and related coatings by the Corrodkode procedure. The method is primarily applicable to copper-nickel-chromium or nickel-chromium electroplated parts.

Specifies a method of boiling specimens in water of known electrical conductivity. Any increase in conductivity indicates residual salt and other conducting impurities.

Specifies a method for the measurement of the thickness of thin, highly reflective coatings (up to 2 ) by the use of Fizeau muliple-beam interferometry. The method described cannot be applied to vitreous enamel coatings. Gives principle, definitions, equipment, factors affecting in the measuring accuracy, calibration, procedure and measuring precision.

Specifies a method for assessing the resistance of materials or products to condensed moisture containing sulfur dioxids. The method has been found to be suitable for testing metallic and non-organic coatings. Gives apparatus and material, test specimens, methods of exposure, procedure, test duration, cleaning of specimens, evaluation of results and test report.

Specifies a method for the measurement of the local thickness of metallic coatings by examination of cross-section with a scanning electron microscope. It is destructive and has an uncertainty of less than 10 % or 0,1 /um, whichever is greater. It can be used for thicknesses up to several millimetres, but it is usually more practical to use a ligth microscope (ISO 1463). Annex a gives the preparation of cross-sections.

Specifies five electrographic tests for assessing the porosity of these gold and gold alloy coatings for engineering, and decorative and protective purposes. The methods are: cadmium sulfide paper test, nioxime paper test, dye-transfer paper test 1 and 2, and electrographic gelatine film test.

The method is based on dissolving the coating on a surface of known area in inhibited acid and determination of the resultant loss in mass by weighing the sample before and after dissolving. Since knowledge of area of the surface is essential, it is mainly applicable to shapes whose areas are easy to determine.

Is limited to qualitative tests. Table 2 indicates the suitablility of each test for some of the most usual types of metallic coatings. Most of the tests are capable of destroying both the coating and the article being tested. Some destroy the coating only, but it should not be assumed that the articles are undamaged. When particular methods of adhesion testing are included in International Standards for individual coatings, they should be used in preference to the methods described in this International Standard.

Applies to coatings of thickness below 200 /um prepared by electroplating, autocatalytic deposition or other processes. The methods of mearuring the ductility can be divided into test on unsupported foils (the foils may consist of one or more metallic layers) and tests of coatings on substrates (with determining the exact point of crack initation of the top layers).

This second edition cancels and replaces the first edition (i. e. ISO 2178:1972). Specifies the method of using coating thickness instruments of the magnetic type for non-destructive measurements of the thickness. The method is applicable only for measurements on reasonably flat specimens. For non-magnetic substrates: see ISO 2361.