Test Background
Filamentous corrosion is a linear corrosion that occurs under a coating of paint, varnish or related products, usually starting from the exposed edges or local damage of the coating. The filamentous corrosion resistance test of steel surface coatings can evaluate the protective effect of steel paint or varnish coatings on preventing filamentous corrosion caused by scratches that penetrate the coating.
Zhongke Testing Reliability Experiment Center has the capability of reliability testing of various paints and varnishes, and provides professional filiform corrosion resistance testing services for steel surface coatings.
Scope of tests
Color paint is divided into primer and topcoat: primer is divided into primer, putty, mid-coat, sealer, anti-rust paint, etc.; topcoat is divided into enamel paint, special topcoat, etc.
The paint and film of varnish are transparent and are divided into ester varnish, shellac varnish, phenolic varnish, alkyd varnish, acrylic varnish, polyester varnish, high-performance varnish, fluorocarbon varnish, etc.
Test method
1. Scratch the painted test panel according to the prescribed method. In order to introduce a small amount of sodium chloride into the scratch, the sample panel can be immersed in a salt solution or exposed to salt spray.
2. Then place the sample in a test chamber with a temperature of 40°C and a relative humidity of 80%. The evaluation criteria for exposure results shall be in accordance with ISO 4628-10 or agreed upon by both parties.
Test standard:
GB/T 13452.4-2008 Paints and varnishes - Filiform corrosion resistance test of coatings on steel surfaces
ISO 4623-1-2018 Paints and varnishes Determination of resistance to filiform corrosion Part 1: Steel substrate
EN ISO 4623-1-2017 Paints and varnishes Determination of resistance to filiform corrosion Part 1: Steel substrate
BS EN ISO 4623-1-2002 Paints and varnishes Determination of resistance to filiform corrosion Part 1: Steel substrate
DIN EN ISO 4623-1-2017 Paints and varnishes Determination of resistance to filiform corrosion Part 1: Steel substrate
