Abstract: The present invention relates to a coating material in the form of a suspension for the coating of metal surfaces of components prior to a thermal treatment for protection against corrosion. The coating material is hereby characterized in that the solid phase of the suspension primarily is composed of aluminum particles, and the liquid phase is composed of organic solvents and binders, the solid phase of the suspension containing at least two types of aluminum particle shapes, which are differentiated by their specific surface. In addition, a component is described, whose metal surface has been coated with a coating material according to the invention prior to thermal treatment and which has a contact resistance of <1 mOhm (DIN EN ISO 18594) after thermal treatment.