ISO 4628-10-2016 pdf free.Paints and varnishes – Evaluation of degradation of coatings – Designation of quantity and size of defects, and of intensity of uniform changes in appearance – Part 10: Assessment of degree of filiform corrosion.
This part of Iso 4628 specifies a method for assessing the amount of filiform corrosion developed from a scribed mark by measuring the length of the longest filament L and the most frequent length M of filaments.
Pictorial examples provided in Annex A of this part of ISO 4628 illustrate different ratings for the length of the longest filament L and the most frequent length M of the filaments. A comparison of the test panels with the 12 pictures in Annex A does not supersede the obligatory numerical assessment (method 1 or 2).
ISO 4628-1 defines a system used for designating the quantity and size of defects and the intensity of uniform changes in appearance of coatings and outlines the general principles of the system. This system is intended to be used, in particular, for defects caused by ageing and weathering, and for uniform changes such as colour changes, for example yellowing.
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 13076. Paints and varnishes — Lighting and procedure for visual assessments of coatings
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
3.1 filiform corrosion type of corrosion proceeding under a coat of paint, varnish, or related product, in the form of threads, generally starting from bare edges or from local damage of the coating
Note ito entry: Usually the threads are irregular in length and direction of growth, but they may also be nearly parallel and of approximately equal length.
Note 2 to entry: Filiform corrosion can also occur under other protective coatings.
Note 3 to entry: Usually the threads follow the direction of extrusion of a metal substrate, do not cross over one
another, and need to be initiated by aggressive ions.
ISOURCE: ISO 4623-1:2000, 3.1, modified — Note 3 to entry has been added; 150 4623-2:2003, 3.1, modified — The notes to entry have been numbered]ISO 4628-10 pdf free download.