This paper develops the extended finite element method (XFEM) to evolve patterns of multiple cracks, in a brittle thin film bonded to an elastic substrate, with a relatively coarse mesh, and without remeshing during evolution. A shear lag model describes the deformation in three dimensions with approximate field equations in two-dimensions. The film is susceptible to subcritical cracking, obeyi...

A numerical study on toughening laminated composite materials against delamination by initiating multiple interlaminar cracks is presented. Different configurations of interface and weakening patches, that modify the properties at selected locations, are investigated as a way to trigger delaminations. Both patches can be configured toughen material The initiation delaminations increase in tough...

Figure 1 Upper two pictures and lower left picture: multiple urothelial cracks seen after hydrodistension, lower right picture: glomerulation (petechiae).

MAX phase materials are emerging as attractive engineering materials in applications where the material is exposed to severe thermal and mechanical conditions in an oxidative environment. The Ti2AlC MAX phase possesses attractive thermomechanical properties even beyond a temperature of 1000 K. An attractive feature of this material is its capacity for the autonomous healing of cracks when opera...

A numerical study is presented of the residual strength of an aircraft fuselage in the presence of multiple site damage (MSD)/muItiple element damage. The analyses were carried out using a software package that was developed to facilitate automated analyses of full-scale fuselage panels with widespread fatigue damage, using a hierarchical approach and elastic-plastic finite element alternating ...

The stress intensity factor solution for embedded circular cracks, semicircular and part-circular surface cracks in plates, quartercircular corner cracks in rods, and semicircular surface cracks at a hole in a plate are evaluated using a finite element alternating method. This method of superposition employs the standard 20-noded solid element solution for the untracked solid, and the complete ...

The propagation of cracks in three dimensions is analyzed by a meshless method. The cracks are modeled by a set of triangles that are added when the propagation occurs. Since the method is meshless, no remeshing of the domain is necessary during the propagation. To avoid using a large number of degrees of freedom, the stress singularity along the front of the cracks is taken into account by an ...

in this research, b4c-ni cermet coating was sprayed on the surface of 4130 steel from b4c and ni feed-stockpowders using high velocity oxy-fuel (hvof) method. in order to characterize the tribological behavior of thecoating, ball on disk wear tests were done at the ambient temperature and under the loads of 1, 3 and 5 n.phase analysis of the coating after spraying was studied by x-ray diffracto...

Fracture modes in a model glass–polymer coating–substrate system indented with hard spheres are investigated. The large modulus mismatch between the glass and polymer results in distinctive transverse fracture modes within the brittle coating: exaggerated circumferential (C) ring cracks that initiate at the upper coating surface well outside the contact (as opposed to the near-contact Hertzian ...

The purpose of this study was to evaluate the generation of enamel cracks and gaps at the cavosurface margin of resin composite restorations using various burs. Saucer-shaped cavities with a bevel were prepared on mid-coronal buccal or lingual surfaces of extracted human molars using a regular-grit round diamond bur, a fine-grit diamond bur, a superfine-grit diamond bur or a six-bladed tungsten...