Influence of the interphase between laser-cladded metal layer and steel substrate on the fatigue propagation of a short edge crack

Laser cladding is a relatively new technology used to combine properties of various materials. As a result, bi-material interfaces now occur in real structures and can affect fatigue crack propagation. A cracked bar subjected to pure tensile loading is numerically simulated in this work in order to analyze the effect of the interphase layer between the cladded metal layer and the steel substrate on crack growth in the surface layer. Particularly, the influence of various Young s moduli of the interphase on stable/unstable edge crack propagation is assessed. Moreover, the number of cycles necessary for the achievement of the defined critical crack length is calculated, and it is concluded that a good knowledge of the elastic properties of the thin interphase is crucial for fracture and fatigue analyses.