Abstract An efficient approach based on the path-independent interaction-integral ( I -integral) is suggested for assessing crack tip loading in elastic structures without having to geometrically model a physical crack. Exploiting just solution of uncracked structure, -integral adapted incorporating closed formulation stress and displacement fields an auxiliary crack, which this interpreted as ...

High-cycle fatigue (HCF), involving the premature initiation and/or rapid propagation of small cracks to failure due to high-frequency cyclic loading, has been identified as one of the leading causes of turbine engine failures in aircraft. In this work, we consider the feasibility of using grain-boundary engineering to improve the HCF properties of a polycrystalline nickel-base superalloy, René...

Fatigue crack growth can be strongly influenced by crack closure, i. e., the contacting of the opposing faces of a fatigue crack above the minimum load in a loading cycle. This crack closure shields the crack tip from the full stress field, but different views are held regarding the extent of this shielding. The type of closure, whether it be plasticity-induced, or roughness-induced may also pl...

The fracture and fatigue characteristics of several cemented carbide grades are investigated as a function of their microstructure. In doing so, the influence of binder chemical nature and content (Co and 76wt%Co-24wt%Ni), as well as carbide grain size on hardness, flexural strength, fracture toughness and fatigue crack growth (FCG) behavior is evaluated. Mechanical testing is combined with a d...

The impedance of an eddy-current probe changes when the current it induces in an electrical conductor is perturbed by a flaw such as a crack. In predicting the probe signals, it is expedient to introduce idealizations about the nature of the flaw. Eddy-current interaction is considered with an ideal crack having a negligible opening and acting as a impenetrable barrier to electric current. The ...

An interaction integral method for evaluating mixed-mode stress intensity factors (SIFs) for two dimensional crack problems using NURBS-based isogeometric analysis method is investigated. The interaction integral method is based on the path independent J-integral. By introducing a known auxiliary field solution, the mixed-mode SIFs are calculated simultaneously. Among features of B-spline basis...

Digital twins have the potential to improve future health prognosis and operational safety of engineering structures. However, few studies attempted validate such with experimental data. In this work, two system-level digital twin models for structural capacity degradation are evaluated data from a four-crack fatigue specimen. Each model is based on dynamic Bayesian network, but differ in compl...