A new and powerful indentation hardness (H) approach to evaluating the true stress (σ)-true plastic strain (ε), σ(ε), constitutive behavior of materials is described. Since measurements of H intrinsically probe a wide-range of ε (up to ≈0.5) , accurate assessment of the corresponding yield (σy) stress and strain hardening [σsh(ε)] pose a significant challenge. Extensive elastic-plastic finite ...

Panels using solar power require high reliability, and the residual stress in the solar panel has an important effect on its reliability and lifetime. The finite element method was adopted to simulate the impacts of the rectangular solar panel encapsulation process parameters, such as the elastic modulus, the thickness of adhesive, and the curing temperature on the residual stress in the solar ...

In this work, the structural and elastic moduli properties of ZnFe2O4, Zn0.5Cu0.5Fe2O4, and Ni0.3Cu0.2Zn0.5Fe2O4 ferrites prepared by the citrate method have been investigated. The structuralcharacterization of the samples is evidence for a cubic structure with Fd-3m space group. TheHalder-Wagner analysis was used to study crystallite sizes and lattice strain and also stressand energy density. ...

The objectives of this study were to analyse the effect of inkjet 3-D printing parameters, particularly the splat overlap distance, for the fabrication of defect-free porous Al2O3 ceramic multilayers, and to correlate the resulting porosities with the mechanical properties measured using nanoindentation. An aqua-based alumina ink was used in this study to fabricate the multilayers on dense alum...

We show by atomistic simulations that, in the thermodynamic limit, the in-plane elastic moduli of graphene at finite temperature vanish with system size L as a power law L(-η(u)) with η(u)≃0.325, in agreement with the membrane theory. We provide explicit expressions for the size and strain dependence of graphene's elastic moduli, allowing comparison to experimental data. Our results explain the...

A low relative area change (RAC) of the proximal pulmonary artery (PA) over the cardiac cycle is a good predictor of mortality from right ventricular failure in patients with pulmonary hypertension (PH). The relationship between RAC and local mechanical properties of arteries, which are known to stiffen in acute and chronic PH, is not clear, however. In this study, we estimated elastic moduli o...

Elastic constants and cross-sectional dimensions of imprinted nanolines of poly(methyl methacrylate) (PMMA) on silicon substrates are determined nondestructively from finite-element inversion analysis of dispersion curves of hypersonic acoustic modes of these nanolines measured with Brillouin light scattering. The results for the cross-sectional dimensions, under the simplifying assumption of v...

An analytical model is developed to deduce the elastic and plastic properties of a hemispherical inclusion embedded in surface semi-infinite solid from its indentation response. The differs approaches presented literature by starting expressions for elasto-plastic responses homogeneous solids, adapting them replacing modulus an effective inclusion. accuracy established comparing results with de...

in this research, the effect of wood species and particle size on mechanicalproperties of wood plastic composites (wpc) made of fir (abies alba) and beech(fagus orientalis l.) sawdust and high density polyethylene (hdpe) wereinvestigated. wood plastic composite (wpc) were made with 30% hdpe in abatch process at 185˚c, at two particle sizes of 40 mesh and 80 mesh. maleicanhydride polypropylene (...

In this paper, a numerical analysis of stresses and displacements in FGM thick-walled cylindrical pressure vessel under internal pressure has been presented. The elastic modulus is assumed to be varying along the longitude of the pressure vessel with an exponential function continuously. The Poisson’s ratio is assumed to be constant. Whereas most of the previous studies about FGM thick-walled p...