We develop in this Note a homogenization method to tackle the problem of a diffusion process through a cracked medium. We assume that the cracks are orthogonal to the surface of the material, where an incoming heat flux is applied. The cracks are supposed to be of depth 1, of small width, and periodically arranged. We show that the cracked surface of the domain induces a volume source term in t...

In this research, plasma electrolytic oxidation (PEO) coatings were prepared on 7075 Al alloy in a silicate-based solution with Na2MoO4 additive using unipolar waveform at constant current density. The displayed micro-pores, micro-cracks, pancake-like and crater-like features, also solidified molten oxide particles the surface. majorly composed of Al2O3 (γ, δ, α), SiO2 (amorphous), MoO3 phases,...

Models of surface fractures due to volcanic loading of an elastic plate are commonly used to constrain the thickness of planetary lithospheres, but discrepancies exist in predictions of the style of initial failure and in the nature of subsequent fracture evolution. In this study, we perform an experiment to determine the mode of initial failure due to the incremental addition of a conical load...

The resonance phenomenon observed in Rayleigh wave scattering from surface-breaking cracks has been investigated using Freund's results on reflection of Rayleigh waves from an infinite crack edge. To model the crack as a section of acoustic waveguide, resonances are treated as standing waves in the length and depth directions. The model takes both faces of the crack into consideration, and this...

Advanced artificial flaw manufacturing method has become available. The method produces true fatigue cracks, which are representative of most service-induced cracks. These cracks can be used to simulate behaviour of realistic cracks under service conditions. This paper introduces studies of the effects of different thermal loading cycles to crack opening and residual stress state as seen at the...

Deformation damage during tension and compression were revealed using in-situ neutron diffraction for a high manganese steel: (1) When the tensile stress is increased, an indication of provided when 111 422 lattice strains along transverse direction give no more contraction or even expansion. This because that replacement slip twinning activities by crack propagation induces relaxation, which c...

During the fabrication of nanopost arrays for measuring cellular forces, we have observed surface cracks in the negative molds used to replicate the arrays from a silicon master. These cracks become more numerous and severe with each replication such that repeated castings lead to arrays with missing or broken posts. This loss in pattern fidelity from the silicon master undermines the spatial r...

Cracks that occur over time are difficult to detect and repair, they threaten the safety durability of buildings limit sustainable building design. This study investigates feasibility using hydroxyapatite (HAp) with graphene oxide silver nanoparticles self-heal narrow cracks detect. Ultrasonic pulse velocity, compressive strength, portlandite content, percentage water absorption porosity recove...