Search Results - "Colak, Ozgen U."

Modelling effects of degree of crystallinity on mechanical behavior of semicrystalline polymers by Dusunceli, Necmi, Colak, Ozgen U.

“…Viscoplasticity theory based on overstress (VBO) which is one of the unified state variable theories is extended to account for crystallinity ratio ( ϕ) on…”
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Experimental investigation of oligo cyclic compression behavior of pure epoxy and graphene-epoxy nanocomposites by Colak, Ozgen U., Uzunsoy, Deniz, Bahlouli, Nadia, Francart, Charles

“…The loading–unloading compression behavior and the oligo cyclic behavior of pure epoxy and graphene-epoxy nanocomposites are investigated since the systematic…”
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Functionalized graphene–epoxy nanocomposites: experimental investigation of viscoelastic and viscoplastic behaviors by Colak, Ozgen U., Birkan, Besim, Bakbak, Okan, Acar, Alperen, Uzunsoy, Deniz

“…In this work, graphene–epoxy nanocomposites are produced for two different graphene fractions (0.1 and 0.5 wt%). Three-roll milling is used as the main…”
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Modeling deformation behavior of polymers with viscoplasticity theory based on overstress by Colak, Ozgen U.

“…The nonlinear strain rate sensitivity, multiple creep and recovery behavior of polyphenylene oxide (PPO), which were explored through strain rate-controlled…”
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Cooperative viscoplasticity theory based on the overstress approach for modeling large deformation behavior of amorphous polymers by Çolak, Ozgen U, Ahzi, Saïd, Remond, Yves

“…A micromechanically based formulation of the cooperative model is incorporated into Viscoplasticity Theory Based on Overstress Model (VBO). Thermo‐mechanical…”
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Modeling of hydro-thermo-mechanical behavior of Nafion NRE212 for Polymer Electrolyte Membrane Fuel Cells using the Finite Viscoplasticity Theory Based on Overstress for Polymers (FVBOP) by Colak, Ozgen U., Acar, Alperen

“…The primary aim of this work is to present the modifications made to the Finite Viscoplasticity Theory Based on Overstress for Polymers (FVBOP). This is a…”
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High density polyethylene (HDPE) : Experiments and modeling by DUSUNCELI, Necmi, COLAK, Ozgen U

“…The uniaxial tension (loading and unloading), creep and relaxation experiments on high density polyethylene (HDPE) have been carried out at room temperature…”
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High strain rate behavior of graphene-epoxy nanocomposites by Colak, Özgen U., Bahlouli, Nadia, Uzunsoy, Deniz, Francart, Charles

“…This work consists of the synthesis of high purity graphene nanoflakes (GNF), the manufacturing of GNF-epoxy nanocomposites and the mechanical characterization…”
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Modeling of the monotonic and cyclic Swift effects using an isotropic, finite viscoplasticity theory based on overstress (FVBO) by Colak, Ozgen U., Krempl, Erhard

“…The simulation of free-end torsion effects of a tubular specimen using isotropic, FVBO is presented. The limited capability of isotropic formulations to model…”
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Modeling of the monotonic and cyclic swift effects using anisotropic finite viscoplasticity theory based on overstress (AFVBO): Part I––Constitutive model by Colak, Ozgen U.

“…The isotropic finite viscoplasticity theory based on overstress (FVBO) is extended to anisotropy. It is accomplished by formulating an anisotropic flow law,…”
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Modeling of monotonic and cyclic Swift effect using anisotropic finite viscoplasticity theory based on overstress (AFVBO): Part II––Numerical experiments by Colak, Ozgen U

“…Anisotropic finite VBO given in Part I is used to model monotonic and cyclic Swift effects. The simulations were performed for fixed and deformation induced…”
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Cooperative-VBO model for polymer/graphene nanocomposites by Acar, A., Colak, O., Correia, J.P.M., Ahzi, S.

“…•A unified elasticity modulus definition which covers all the effects is obtained.•For visco-plastic deformation, three material parameters are re-defined.•The…”
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Determination of material parameters of a viscoplastic model by genetic algorithm by Dusunceli, Necmi, Colak, Ozgen U., Filiz, Coskun

“…Macroscopic (continuum) and microscopic models, used for simulation of material behaviors under different loading conditions, contain a large number of…”
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Kinematic hardening rules for modeling uniaxial and multiaxial ratcheting by Colak, Ozgen U.

“…Ratcheting, which is the strain accumulation observed under the unsymmetrical stress controlled loading and non-proportional loadings, is modeled using the…”
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Phytotoxicity of graphene in tomatoes and bean by Cakir, Yuksel, Colak Cakir, Ozgen U.

“…The potential effects of graphene nano platelet (GNP) on the germination and seedling growth of terrestrial plants such as beans and tomatoes are investigated…”
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Investigation of graphene phytotoxicity in the germination stage of wheat and barley by Cakir, Yuksel, Colak Cakir, Ozgen U.

“…Graphene which is a monolayer of carbon atoms arranged in a two dimensional lattice, has attracted great attention in recent years. Due to its unique…”
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A viscoplasticity theory applied to proportional and non-proportional cyclic loading at small strains by Colak, Ozgen U.

“…The small strain, isotropic, Viscoplasticity theory Based on Overstress (VBO) is modified so that the experimentally observed, complex cyclic hardening…”
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Compressive failure strengths and modes of woven S2-glass reinforced polyester due to quasi-static and dynamic loading by Khan, Akhtar S., Colak, Ozgen U., Centala, Prabhakaran

“…The failure strengths and modes of the woven S2-glass reinforced polyester thick laminate are characterized through a comprehensive set of experiments…”
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Cooperative viscoplasticity theory based on the overstress approach for modeling large deformation behavior of amorphous polymers: Cooperative viscoplasticity theory by Çolak, Ozgen U, Ahzi, Saïd, Remond, Yves

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Makina elemanlarının projelendirilmesi: Atilla Bozacı, Özgen Ü. Çolak, İlknur, Koçaş by Bozacı, Atilla, Koçaş, İlknur, Çolak, Özgen Ü

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