Impact of a single-side 100Cr6 clad layer on the tensile and fatigue properties of S550MC steel

The production of newly developed hot-rolled layered metal composites (LMC) leads to the availability of sheet materials with specifically adjustable, graded properties being cost-effective and suitable for large-scale production. As many of the envisaged applications of these LMC, e.g., clutch disc carriers, suffer from cyclic loading during service life, a fundamental knowledge of the fatigue behavior is required in order to ensure safe and reliable application of the components. Therefore, the present study focuses on the fatigue behavior of a hot-rolled two-layer LMC consisting of a S550MC substrate layer and a 100Cr6 clad layer. In order to investigate the influence of the clad layer, two conditions are directly compared, i.e., the two-layer laminate cladded steel and the single-layer substrate condition. Results presented by mechanical testing include hardness measurements and tensile tests as well as strain-controlled low-cycle fatigue and stress-controlled high-cycle fatigue tests. These results are discussed based on evolution of microstructure, residual stress, and defects, respectively, as elaborated by scanning electron microscopy, X-ray diffraction, and fracture surface analysis.