Paints and coatings of all types are widely used to provide colour and pleasing aesthetics, and to prevent deterioration of the underlying substrate when exposed to various environments. Besides protection and beauty, however, coatings provide light reflectivity, camouflage surfaces, reflect and absorb heat, and provide a variety of other functions. With exposure to environmental parameters, coating degrades over time. This leads to crack initiation, propagation & delamination. If the coating is overheated, it can lead to loss of mass or decomposition and ingress of aqueous media can lead to change in the chemical composition of the coating as well.
ISO 4628-10 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 are provided in ISO 4628-10 to illustrate different ratings for the length of the longest filament L and the most frequent length M of the filaments. An obligatory numerical assessment (method 1 or 2) is required to be conducted in addition to the comparison of the test panels with the 12 pictures provided in ISO 4628-10.
ISO 4628-10 on degradation of coating filiform corrosion standard is useful for:
Most of the protective coatings perform admirably until an old age, at which time natural deterioration and degradation occur. Energy acting on a coating can degrade a material by breaking or interfering with the chemical bonds holding the resin together and to a substrate.
ISO 4628-10 guides you with assessment techniques to evaluate the degradation of coatings and designate the quantity and size of defects in terms of intensity of uniform changes in appearance, the degree of filiform corrosion. This helps you to design better products and mitigate weathering challenges for coatings, so that your customers can enjoy long lasting products.
BS EN ISO 4628-10:2016 supersedes BS EN ISO 4628-10:2003. BS EN ISO 4628-10:2016 includes some technical changes with respect to BS EN ISO 4628-10:2003. These include: