The failure due to accidental drop of magnetic recording disks made of brittle or ductile materials is of great interest in the design of small form factor hard disk drives. In this study, fracture of glass disks (brittle material) and plastic deformation of aluminum disks (ductile material) at very high shock levels caused by accidental drop are investigated using finite element analysis. It i...

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...

With the construction of supertall buildings such as high earth dams, linear envelope Mohr-Coulomb (M-C) failure criterion fitted to lower confined pressure would significantly underestimate loading capacity foundations, causing a huge increase in amount earthwork. Given that M-C has dominated stability analysis geotechnical structures, it is proposed this study remain invariant form but cohesi...

Understanding the grain size-dependent failure behavior of polycrystalline graphene is important for its applications both structurally and functionally. Here we perform molecular dynamics simulations to study the failure behavior of polycrystalline graphene by varying both grain size and distribution. We show that polycrystalline graphene fails in a brittle mode and grain boundary junctions se...

conclusions parametric models may provide complementary data for clinicians and researchers about how risks vary over time. the weibull model seemed to show the best fit among the parametric models of the survival of hemodialysis patients. results the results of a multivariate analysis of the variables in the parametric models showed that the mean serum albumin and the clinic attended were the ...

On the base of physical-and-mechanical modelling for cleavage microcrack behaviour a new local criterion for cleavage fracture is formulated. Cleavage fracture of pressure vessel steel under various loading history is investigated. It has been experimentally shown that for steels after static prestrain by tension and cyclic prestrain brittle fracture critical stress is described by increasing f...

The Master Curve brittle fracture toughness estimation method described in the ASTM E1921-11 test standard is based on a theoretical scatter and size effect assumption and makes use of a maximum likelihood estimation method to determine the fracture toughness transition temperature T0. The estimation method in E1921-11 is valid only for macroscopically homogeneous steels. If the steel is inhomo...

It is generally observed that the existence of geometrical discontinuity like notches in materials will lead to strength weakening, as a resultant of local stress concentration. By comparing the influence of notches to the strength of three typical materials, aluminum alloys with intermediate tensile ductility, metallic glasses with no tensile ductility, and brittle ceramics, we observed streng...