Loading...
Search for:
effective-mechanical-properties
0.006 seconds
Critical state concepts for a cemented gravely sand
, Article Electronic Journal of Geotechnical Engineering ; Volume 10 E , 2005 ; 10893032 (ISSN) ; Haeri, S. M ; Sharif University of Technology
2005
Abstract
The shear behavior of a cemented gravely sand that can be considered as the representative of Tehran alluvium has been studied using triaxial equipment. Artificially cemented samples were prepared using gypsum plaster as the cementing agent. The plaster was mixed with the base soil at the weight percentages between 1.5 and 6. The critical state concepts were used to illustrate the mechanical behavior of tested soil. © 2005 ejge
Effects of surface elasticity on 3D micromechanical modeling of short fiber nanocomposites
, Article 2012 3rd International Conference on Manufacturing Science and Technology, ICMST 2012, New Delhi, 18 August 2012 through 19 August 2012 ; Volume 622 , 2013 , Pages 975-979 ; 10226680 (ISSN) ; 9783037855638 (ISBN) ; Naghdabadi, R ; Sharif University of Technology
2013
Abstract
Recent studies have shown that the surface/interface free energy plays an important role in the effective mechanical properties of solids with nanosized inhomogeneity. In the present study, an analytical model is developed for 3D axisymmetric analysis of short fiber nanocomposites including the fiber end region, subjected to an applied axial load considering surface effects. Closed form expressions are obtained for 3D stress filed in the fiber and matrix. Moreover, performing numerical examples, it is shown that the elastic stress field is size dependent in both the fiber and matrix especially for fiber radii less than 50 nm
Effects of surface residual stress and surface elasticity on the overall yield surfaces of nanoporous materials with cylindrical nanovoids
, Article Mechanics of Materials ; Volume 51 , 2012 , Pages 74-87 ; 01676636 (ISSN) ; Naghdabadi, R ; Asghari, M ; Sharif University of Technology
Elsevier
2012
Abstract
Mechanical properties of a material near the surfaces and interfaces are different from those of the same material far from the surfaces/interfaces. The effect of this difference on the effective mechanical properties of heterogeneous materials becomes significant when the size of inhomogeneities is at the scale of nanometers. In this article, within a micromechanical framework, the effects of surface residual stress and surface elasticity are taken into account to obtain a macroscopic size-dependent yield function for nanoporous materials containing aligned cylindrical nanovoids. Based on the modified Hill's condition, the strains are decomposed into two parts, a part due to the external...
Effect of casting process on microstructure and tribological behavior of LM13 alloy
, Article Journal of Alloys and Compounds ; Volume 475, Issue 1-2 , 2009 , Pages 321-327 ; 09258388 (ISSN) ; Niroumand, B ; Karimzadeh, F ; Hamani, M ; Pouranvari, M ; Sharif University of Technology
2009
Abstract
LM13 alloy is widely used in piston industry, due to its low coefficient of thermal expansion, excellent castability and hot tear resistance. In this research effect of casting process on wear behavior of LM13 alloy was investigated. First, samples were produced using two casting processes and heat treated. Then wear behavior of these samples under dry sliding condition was examined. Results of hardness and strength tests indicated that squeeze cast specimens exhibited higher mechanical properties. Wear experiment results showed that in both squeeze and gravity cast specimens, amount of weight loss increases with increase in sliding distance which is accompanied by reduction in wear rate and...
Effect of interphase zone on the overall elastic properties of nanoparticle-reinforced polymer nanocomposites
, Article Journal of Composite Materials ; Volume 53, Issue 9 , 2019 , Pages 1261-1274 ; 00219983 (ISSN) ; Jam, J. E ; Arab, B ; Firouz Abadi, R. D ; Sharif University of Technology
SAGE Publications Ltd
2019
Abstract
In the current work, the effect of interphase region on the mechanical properties of polymer nanocomposites reinforced with nanoparticles is studied. For this purpose, a closed-form interphase model as a function of radial distance based on finite-size representative volume element is suggested to estimate the mechanical properties of particle-reinforced nanocomposites. The effective Young’s and shear moduli of thermoplastic polycarbonate-based nanocomposites for a wide range of sizes and volume fractions of silicon carbide nanoparticles are investigated using the proposed interphase model and molecular dynamics simulations. In order to investigate the effect of particle size, several unit...
The effective mechanical properties and the interfacial characterization of CNT reinforced nanocomposites
, Article Proceedings of SPIE - The International Society for Optical Engineering, 9 March 2009 through 11 March 2009, San Diego, CA ; Volume 7294 , 2009 ; 0277786X (ISSN); 9780819475541 (ISBN) ; Naghdabadi, R ; The International Society for Optical Engineering (SPIE) ; Sharif University of Technology
2009
Abstract
A small volume fraction of Carbon Nanotubes (CNTs) added in a polymeric matrix increases significantly the mechanical properties of the polymers. It is experimentally determined from the TEM images of CNT-based nanocomposites that nanotubes don't stand straight in their embedded matrix and they have some curvature in their shape. The load transfer mechanism between CNT and polymer matrix is also one of the most important issues which is not understood explicitly, yet. In this paper a wavy Single Walled Carbon Nanotube (SWCNT) is modeled as inclusion in a polymer matrix and its effective mechanical properties is studied. This model is based on using 3-D Representive Volume Element (RVE) with...