Filiform corrosion is a special corrosion phenomena that often affects coated aluminum and low alloy steels. The corrosion creeps between the metal and the coating, typically in the shape of fine filaments.
During the development of coating systems with improved corrosion resistance as well as for quality control of coated components, a large number of coated test plates is produced. These plates are scribed and then weathered in special climate chambers to start the corrosion.
Conventionally, the resulting corrosion phenomena are then manually and visually evaluated, often using a magnification glass with an integrated scale, a very tedious work, which is error-prone and subjective. The Corrosion Inspector scans a standardized test plate in 0.8 seconds with an optical resolution of 0.04 mm.
The coaxial illumination, either as a bright field or as a dark field, ensures the high contrast image of the corrosion structures. The software automatically detects the shape, length and corrosion area and evaluates it according to the relevant standards.
The system was developed for rapid and objective corrosion evaluations with high sample throughput. The automatic evaluation takes 2 -3 seconds. Including documentation in an image and Excel sheet, the test process for a sample plate is completed in 5 seconds.