Influence of corrosion fatigue on the fatigue strength of an AlSi10MgMn high‐pressure die‐casting alloy with regard to the surface condition

Abstract

AbstractThis study investigates the influence of corrosion fatigue on the fatigue strength of an AlSi10MgMn high‐pressure die‐casting alloy with regard to the surface condition. Two different surface conditions are compared. First, an unmachined surface condition with a rough surface () and second a machined and polished surface condition with a smooth, polished surface () are tested. The specimens are loaded with a cyclic bending moment at a constant stress ratio of R = 0 till failure. A 5 wt% NaCl solution enables the corrosion fatigue tests. Corrosion fatigue leads to a significant reduction of the endurable stresses along the whole load spectrum independent from the surface condition. The applied corrosive solution prevents the formation of a pronounced long‐life fatigue strength limit within the tested load cycle range. Hence, the reduction of the endurable stresses increases with the increasing number of load cycles, reaching approximately 37% at load cycles. No significant influence of the surface condition, independent of the environment (air, 5 wt% NaCl), on the fatigue behaviour is found.