Ahmed Al-Ostaz

Learn More
The variation of arrangement of micro-structural entities (i.e. inclusions) influences local properties of composites. Thus, there is a need to classify and quantify different micro-structural arrangements. In other words, it is necessary to identify descriptors that characterize the spatial dispersion of inclusions in random composites. On the other hand,(More)
This paper describes investigations on dynamic mechanical analysis (DMA) of nylon 6,6 thermoplastic reinforced with 1.25 and 2.5 wt. percent multi-wall carbon nano tubes (MWCNT), and Derakane 411-350 vinyl ester thermoset reinforced with 1.25 and 2.5 wt. percent Cloisite 30B nanoclay and exfoliated graphite nanoplatelets (xGnP). Visco-elastic materials(More)
Polyetherimide (PEI)-graphene nanoplatelet (GNP) (PEIGNP) papers, with extremely high GNP loadings (up to nearly 100 wt%), were produced by filtration and hot-press. The impact of the GNP content on the impedance and mechanical properties, such as damping behavior, was investigated. Although the PEIGNP papers showed some decreases in tensile strength and(More)
We conduct a finite element analysis of the slice compression test [13] applied to metal-matrix composites. This test, designed to characterize interfaces in composite materials, involves pressing a composite material specimen on a soft plate so that fibers are forced to protrude and intrude into the soft plate leaving a permanent deformation. We focus on(More)
Hybrid Lattice Particle modelling (HLPM) is an innovative particular dynamics approach that is established based on a combination of the particle modelling (PM) technique together with the conventional lattice modelling (LM) theory. It is developed for the purpose of simulating the dynamic fragmentation of solids under high strain rate loadings at(More)
We studied a model composite material consisting of a thin epoxy plate (matrix) reinforced with stiff circular disks (inclusions) and subjected to a uniaxial tension. At each inclusion-matrix interface there is an interfacial layer, an interphase, which has uniform properties. The inclusions are arranged in the matrix at random but with no overlap. For(More)
Reactive molecular dynamics simulation was employed to compare the damage mitigation efficacy of pristine and polyimide (PI)-grafted polyoctahedral silsesquioxane (POSS), graphene (Gr), and carbon nanotubes (CNTs) in a PI matrix exposed to atomic oxygen (AO) bombardment. The concentration of POSS and the orientation of Gr and CNT nanoparticles were further(More)
  • 1