Browsing by Author "Düşünceli, Necmi"
Now showing items 1-20 of 21
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Cyclic behavior of high density polyethylene (HDPE)
Düşünceli, Necmi; Aydemir, Bülent; Terzi, Niyazi Uğur (American Institute Physics, 2010)This article presents the mechanical behavior of high density polyethylene (HDPE). Samples were prepared by extracting extruded HDPE pipe. Cyclic and strain rate jump behavior of HDPE were studied under uniaxial tensile ... -
Cyclic deformations of polypropylene with a strain-controlled program
Drozdov, Aleksey; Düşünceli, Necmi (Wiley-Blackwell, 2012)Experimental data are reported on isotactic polypropylene in uniaxial tensile cyclic tests with a strain-controlled program (oscillations between fixed minimum and maximum strains). The following characteristic features ... -
Çift ağlı hidrojellerin basma yükü altında gerilme gevşemesi davranışı
Düşünceli, Necmi (TMMOB Makina Mühendisleri Odası, 2021)Akrilamid (AAM) zayıf mekanik özellikleri dolayı, biyodoku iskeleleri ve yumuşak doku aktüatörleri gibi biyomedikal uygulamalarda istenilen özellikleri sergileyememektedir. Bu nedenle Aljinat (ALG) kullanı-larak çift ağa ... -
Determination of material parameters of a viscoplastic model by genetic algorithm
Düşünceli, Necmi; Çolak, Özgen U.; Filiz, Coşkun (Elsevıer Scı Ltd, 2010)Macroscopic (continuum) and microscopic models, used for simulation of material behaviors under different loading conditions, contain a large number of material parameters and determination of these parameters is an important ... -
The effect of polyurethane and carnauba wax on the mechanical and physicochemical properties of acrylonitrile butadiene nitrile rubber coating working gloves
Düşünceli, Necmi; Akyüz, Lalehan; Şahin, Necmettin; Duru, Hatice (Sage Publications Ltd, 2019)In this study, the effect of polyurethane (PU) and carnauba wax (CW) on the mechanical and physicochemical properties of acrylonitrile butadiene nitrile rubber coating gloves was investigated. Thermal decomposition and ... -
The effects of loading history and manufacturing methods on the mechanical behavior of high-density polyethylene
Düşünceli, Necmi; Aydemir, Bülent (Sage Publications Ltd, 2011)This article describes a series of experiments conducted to determine the effects of loading history and manufacturing techniques on mechanical behavior of high-density polyethylene (HDPE). The main reason for undertaking ... -
Evaluation of ınstallation quality on polyethelene pipe performance under surcharge loads
Terzi, Niyazi U.; Düşünceli, Necmi; Yılmaztürk, Ferruh; Yıldırım, Sönmez (American Institute Physics, 2010)In this study, a comprehensive laboratory test on 100 mm diameter HDPE 100 polyethylene flexible pipe buried in quartz sand is described. The laboratory test was performed in a 40 mm thick plexiglass-fronted test tank which ... -
Experimental and numerical analysis of failure crack growth of polypropylene
Düşünceli, Necmi (Huthig GmbH, 2020)Observations were presented on crack growth behavior of polypropylene (PP) on virgin and annealed compact tension (CT) specimens at various loading amplitude. The fracture behavior was evaluated using J integral method. J ... -
Fading memory of deformation history in carbon black-filled thermoplastic elastomers
Düşünceli, Necmi; Drozdov, Aleksey D. (Elsevier, 2017)Observations are reported on a carbon black reinforced thermoplastic elastomer in multistep uniaxial tensile cyclic tests with a mixed deformation program (oscillations between maximum elongation ratios k(max) and various ... -
Influence of temperature on viscoelastic–viscoplastic behavior of poly(lactic acid) under loading–unloading
Düşünceli, Necmi; Drozdov, Aleksey D.; Theilgaard, Naseem (Wiley, 2017)Experimental data are reported on poly(lactic acid) (PLA) in tensile loading-unloading tests and relaxation tests under stretching and retraction at temperatures ranging from room temperature up to 508C. Two characteristic ... -
Mechanical properties of polymer-matrix cellulose-based composite materials
Düşünceli, Necmi; Sürme, Seçkin (Institute of Metals Technology, 2020)This study focuses on composite cardboard panels, determining their mechanical properties. The panels were manufactured of a minced waste-paper-based composite material. First, four types of mixture were prepared using ... -
Modeling finite deformation behavior of semicrystalline polymers under uniaxial loading-unloading
Düşünceli, Necmi (Sage Publications, 2010)The aim of this work is to investigate the finite deformation behavior of polymeric materials under monotonic loading-unloading. The strain rate sensitivity behaviors of polymeric materials were modeled using viscoplasticity ... -
Modeling of multi-cycle deformation of polymers with various deformation programs
Drozdov, A. D.; Düşünceli, Necmi (2013)The purpose of this paper is to compare mechanical response of polypropylene in multi?cycle tensile tests with strain?controlled and mixed deformation programs and to develop constitutive equations that describe quantitatively ... -
An observation of the evolution of equilibrium stress on poly(lactic acid) and poly(lactic acid)/hydroxyapatite nanocomposites
Düşünceli, Necmi (SAGE Publications Ltd, 2021)Relaxation behavior provides specific information that indicates stress development with elapsed time for the determination of material characterization and constituting of material modeling. In addition, anomalous relaxation ... -
Polimer malzemelerin hasar birikimine bağlı mekanik davranışlarının incelenmesi
Özensoy, Önder Çağdaş (Aksaray Üniversitesi Fen Bilimleri Enstitüsü, 2022)Son yıllarda mühendislik yapılarında polimerik malzemelerin uygulamaları oldukça artmıştır. Bu nedenle polimerik malzemelerin elastik olmayan deformasyon mekanizmasını anlamaya yönelik çalışmaların sayısı da oldukça çok ... -
Polimerik matrisli selüloz esaslı kompozit geri dönüşüm malzemelerinden üretilmiş levhaların mekanik özelliklerinin belirlenmesi
Sürme, Seçkin (Aksaray Üniversitesi Fen Bilimleri Enstitüsü, 2016)Bu tez çalışması, geri dönüşüm yolu ile elde edilen kompozit kağıt malzemelerin yüksek yoğunluklu polietilen ile farklı oranlarda karıştırılması ile elde edilen karışımın sıcak presleme vasıtasıyla üretilmiş olan plakaların ... -
Self-recovery and fatigue of double-network gels with permanent and reversible bonds
Drozdov, Aleksey; Christiansen, Jesper deClaville; Düşünceli, Necmi; Sanporean, Catalina-Gabriela (WILEY, 2019)Double-network (DN) gels subjected to cyclic deformation (stretching up to a fixed strain followed by retraction down to the zero stress) demonstrate a monotonic decrease in strain with time (self-recovery). Observations ... -
Thermo-mechanical response of poly (lactic acid)/hydroxyapatite nanocomposites: Observations and modeling within the overstress concept
Düşünceli, Necmi; Drozdov A.D.; Theilgaard N. (2013)Experimental investigation and constitutive modelling are conducted of the mechanical response of poly (lactic acid) (PLA)/hydroxyapatite (HA) nanocomposites at temperatures ranging from room temperature up to 50 °C. PLA ... -
Universal mechanical response of polypropylene under cyclic deformation
Drozdov, Aleksey; Düşünceli, Necmi (WALTER DE GRUYTER GMBH, 2012)Experimental data are reported on isotactic polypropylene in uniaxial tensile (i) cyclic tests (oscillations between maximum strain 0.15 and the zero minimum stress) with various cross-head speeds and (ii) relaxation tests ... -
The unusual creep and relaxation behaviour of polypropylene
Düşünceli, Necmi (Walter de Gruyter, 2012)This paper focuses on experimental investigation and modelling of the unusual creep and relaxation behaviour of polypropylene. A polypropylene specimen was loaded up to three different levels of maximum strain (ɛmax), ...
