with details of the nature of the infringement. We will investigate the claim and if justified, we will take the appropriate steps.

The anodising process parameters (voltage, temperature, and electrolyte) control the morphology and the chemical composition of the resulting anodic oxide film by altering the balance between oxide growth and oxide dissolution reactions. The porosity of the oxide film is reduced by the addition of tartaric acid to a sulfuric acid electrolyte, while anodising at elevated temperatures enhances oxide dissolution, leading to wider pores and rougher surfaces. No significant changes in the oxide chemical composition as a function of anodising parameters was found; in particular, no tartrate incorporation took place. The resistance of uncoated anodic oxide films against aggressive media and galvanic stress as a function of anodising parameters has been studied by electrochemical methods. Anodising in a mixed tartaric and sulfuric acid electrolyte improves the resistance of the anodic oxide against galvanic stress and aggressive media in comparison to sulfuric acid anodising processes. However, the corrosion protection performance of the anodic oxide films in combination with a corrosion-inhibitor loaded organic coating is not governed by the blank oxide properties but by the adhesion-enhancing morphological features formed during anodising at elevated temperatures at the oxide/coating interface.

Aluminum is an appropriate candidate for bipolar plates in proton exchange membrane (PEM) fuel cells because it reduces the final cost and weight of the fuel cell stack in comparison to stainless steel, titanium and graphite. However, a conductive coating layer is essential to protect it against corrosion. In this study, the electrochemical behavior of aluminum coated with titanium and amorphous carbon layers by physical vapor deposition is evaluated. The main goal is to investigate the corrosion protection performance and the possible failure reasons of the coating in sulfuric acid solutions (with different pH values) in the presence of 3 ppm sodium fluoride and elevated temperature (80 • C) to mimic the working conditions of PEM fuel cells. To reach our aim, electrochemical tests are combined with surface analysis techniques. It is revealed that at low pH values (pH= 2 and 3), the coating fails due to the acidity of the electrolyte solutions. However, in the electrolyte with pH= 4, present fluoride ions interfere and consequently lead to localized failures. It is noticed that the presence of defects in the coating is a key parameter in the application of coated aluminum as bipolar plates in PEM fuel cells.

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