Monitoring of Technological Factors to Change the Length of the Crack Created by Cataphoretic Coating

Cataphoresis, also called E-coating, electrocoating or electrophoretic coating, is the process of applying a concentration of high-quality epoxy resins and pigments to electrically conductive surfaces in order to increase the materials’ resistance to corrosion using electrochemical principles. Thus, electrolytic deposition is the most suitable method for creating an anti-corrosion protective layer on metal surfaces with complex shapes. Through this method, it is possible to ensure uniformity and a smooth anti-corrosion coating, regardless of the shape and complexity of metal surfaces. The aim of this research was to analyze the influence of more critical factors affecting the crack length found. In the planned experiment, samples made of steel type VDA 239–100 CR4, CR5 were used. A total of 88 separate samples were made in accordance with the Design of Experiments methodology using a central composite plan. For sample 83, the technological operation of chemical degreasing was omitted, and for sample 84, in addition to degreasing, activation and phosphating were also performed. During the bending test, the concentration factors of the degreasing solution and the deposition time in the degreasing solution were monitored. The results were displayed in graphical dependencies.