Out-of-plane, nanoscale periodic corrugations are observed in the dynamic fracture surface of brittle bulk metallic glasses with fracture toughness approaching that of silica glasses. A model based on the meniscus instability and plastic zone theory is used to explain such dynamic crack instability. The results indicate that the local softening mechanism in the fracture is an essential ingredie...

In this study, a novel numerical method is proposed for determination of mode-I interlaminar fracture toughness, GIc, in multi-directional (MD) double cantilever beam (DCB) specimens using fracture properties of unidirectional DCB specimens. Two factors, β and Dc are defined to minimize the undesirable effects on strain energy release rate. β describes the difference between maximum and average...

A new test method has been developed to measure the resistance of dynamic fracture initiation in brittle materials under combined mode I/I loadings. The Brazilian disks with center-cracks have been fractured under oblique impact loadings in diarnetral-compression. The dynamic stress intensity factors of mode I and H are evaluated from the superposition integrals of the step response functions f...

Leaves as the main photosynthetic organ of plants must be well protected against various hazards to achieve their optimal lifespans. Yet, within-species variation and the material basis of leaf strength have been explored for very few species. Here, we present a large dataset of leaf fracture toughness from a species-rich humid tropical forest on Barro Colorado Island, Panama, reporting both am...

Natural and artificial materials including rocks and cement-based materials such as concrete and cement mortar are affected both physically and chemically by various natural factors known as weathering factors. The freeze-thaw process, as a weathering factor, considerably affects the properties of rocks and concrete. Therefore, the effect of the freeze-thaw process on the physical and mechanica...

The synergistic effects of reactive polyol diluent and amino-functionalized multi-walled carbon nano-tubes on fracture of two-and three-phase (hybrid) epoxy nanocomposites are investigated under quasi-static and dynamic loading conditions. Digital image correlation method with a drop-tower and high-speed camera are used for dynamic tests. The crack-tip deformation histories and fracture paramet...

A hybrid finite-discrete element method (FDEM) is proposed to model rock fracture initiation and propagation during a three-point bending test under quasistatic dynamic loading conditions. Three models have been implemented in the FDEM transition from continuum discontinuum through fragmentation. The rate effect on behaviour has taken into account by implementation of relationship between stati...

The fracture toughness of SLG filled phenolic composites have been determined by short bar tests. It is expensive to prepare the samples for the tests. Therefore, it is necessary to develop a mathematical model that will predict the fracture toughness of particulate filled phenolic composites. Mathematical models for tensile strength, Young’s modulus are available but not for impact strength an...