Evaluation of Ductile Crack Propagation Behavior for Subsurface Crack in Cladded Plates Using XFEM

<jats:p>In petrochemical and nuclear power plants, inner surface of components, such as pressure vessels and piping, which are made of carbon steels or low-alloy steels, is often cladded by austenitic stainless steels to improve the corrosion resistance of those components. In the evaluation of a crack postulated near the inner surface of cladded components, the following two different kinds of cracks are often assumed: One is a surface crack penetrated through cladding and the other is a subsurface crack under cladding. In order to evaluate the structural integrity of those components in a rational manner, it is important to investigate the crack propagation behavior. In particular, it should be evaluated whether a subsurface crack penetrates through cladding or is arrested at the interface between cladding and base metal. In this study, ductile crack propagation analysis for a subsurface elliptical crack in cladded plates was performed using elastic-plastic XFEM, which can model the crack independent of finite elements.</jats:p>