In the present research, a fully Automatic crack propagation as one of the most complicated issues in fracture mechanics is studied whether there is an inclusion or no inclusion in the structures. In this study The Extended Finite Element Method (XFEM) is utilized because of several drawbacks in standard finite element method in crack propagation modeling. Estimated Crack paths are obtained by ...

ÐFatigue crack initiation and multiplication of the unnotched SCS-6 silicon carbide ®ber-reinforced titanium matrix composites with di€erent matrix and interfacial properties have been investigated experimentally and analytically. Ti±15V±3Al, Ti±6Al±4V, and Ti±22Al±23Nb were chosen as matrix materials. The initiation and propagation of each individual matrix crack as a function of fatigue cycle...

The natural initiation and growth of short cracks in Inconel 718 U-notch specimens has been studied at 600C in air. U notches were introduced through broaching, and hardness traces and optical microscopy on cross sections through the U notch broaching showed that the broaching process had introduced a deformed, work hardened layer. Fatigue tests were conducted under load control using a 1-1-1-1...

Nowadays total joint replacements are widely used in the world, so in average 800,000 joint surgeries are done yearly only in Europe and North America. However implant loosening is and remains as the major issue of all implant failures and therefore causes revision surgery procedures. Studies and experiments have identified poor fixation of implants most likely is the main cause of long term im...

Recent research shows that macro-scale cracking in asphalt binder may originate from its intrinsic defects at the nano-scale. In this paper, a molecular dynamics (MD) simulation was conducted to evaluate the nucleation of natural defects in asphalt. The asphalt microstructure was modeled using an ensemble of three different types of molecules to represent a constituent species: asphaltenes, nap...

This paper outlines a new durability model to assess the most economical first inspection period for structures. Practical scatter factor formulae are presented to determine the safe fatigue crack initiation and propagation lives from the result of a single full-scale test of a complete structure. Theoretical prediction techniques are developed to establish the relationship equation between the...

We analyze the initiation and propagation of a crack from a point on the surface of a circular notch-tip in an impact loaded prenotched plate. The material of the plate is assumed to exhibit strain hardening, strain-rate hardening, and softening due to the rise in temperature and porosity. The degradation of material parameters due to the evolution of damage in the form of porosity is considere...

The characterization of critical levels of microstructural damage that can lead to fatigue-crack propagation under high-cycle fatigue loading conditions is a major concern for the aircraft industry with respect to the structural integrity of turbine engine components. The extremely high cyclic frequencies characteristic of in-flight loading spectra necessitate that a damage-tolerant design appr...