For the reliable and economical use of brazed components under mechanical loads in corrosive environments, the understanding of the alloy-process-structure-property relationship is elementary. In this study, three different nickelbased alloys in form of rapidly quenched foils with alternating chromium and molybdenum content were produced and used for brazing cylindrical butt joints at two different holding times at 1160℃, resulting in six microstructures. Different phases such as borides and silicides could be observed, which differed in terms of size, quantity, and location. Corrosion fatigue tests were carried out using a servo-hydraulic fatigue testing system in a self-designed corrosion chamber that was constantly flowed through by a moderate synthetic exhaust gas condensate. In addition to tactile strain measurements, the electrochemical open-circuit potential was recorded to obtain information about passive layer development and crack mechanisms. Furthermore, pure corrosion tests were carried out to separate corrosive properties from mechanical ones. It was shown that a high chromium content can increase the corrosive resistance, but it can also contribute to undesirable phase formations and therefore reduce the fatigue lifetime, especially if a short holding time during the brazing process was applied. Finally, fractographic investigations enabled an understanding of the fracture mechanisms.
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