Yazar "Oral, Imran" seçeneğine göre listele
Listeleniyor 1 - 10 / 10
Sayfa Başına Sonuç
Sıralama seçenekleri
Öğe Characterization of unmodified and modified apricot kernel shell/epoxy resin biocomposites by ultrasonic wave velocities(Springer, 2023) Oral, Imran; Kocaman, Suheyla; Ahmetli, GulnareThe main goal of this research was to develop highly durable, low-cost eco-friendly biocomposites from apricot kernel shell (AKS) wastes and ultrasonic characterization of AKS-based obtained biocomposites. Natural AKS wastes were chemically modified using 5 wt% sodium hydroxide (NaOH) and 99 wt% glacial acetic acid (AA). These modified apricot kernel shells (MAKS) and unmodified apricot kernel shells (UMAKS) were added into bisphenol-A type epoxy resin (ER) in varied compositions such as 10-50 wt% to prepare the MAKS/ER and the UMAKS/ER biocomposites. The epoxy resin-mixture in the weight ratios of resin/hardener/accelerator was 100:30:1. The effect of AKS powder ratios and modifiers on the elastic properties (Young's moduli [E], bulk moduli [K], longitudinal moduli [L], shear moduli [G], and Poisson's ratio [mu]), density (rho), damping properties (attenuation coefficient [alpha], loss tangent [tan delta], and quality factor [Q]), ultrasonic micro-hardness (H), and acoustic impedance (Z) of biocomposites was investigated by the ultrasonic testing (UT) method. The morphological structure of the ER and biocomposites was figured out using scanning electron microscopy (SEM) and X-ray powder diffraction (XRD). The results revealed an increase in elastic properties of most of the AKS/ER biocomposites compared to the neat ER. On the other hand, results have shown that SEM and XRD images' analysis confirmed the amorphous structure of ER and biocomposites. The highest rho, v(L), v(S), L, G, E, H, and Z values were obtained in MAKS-AA/ER-5 biocomposite. Thus, it can be stated that the MAKS-AA/ER-5 biocomposite sample has the best mechanical properties. Also, the results revealed that the MAKS-AA/ER-1 sample can be used as an alternative material for its high Q-factor value instead of wood in producing musical tools.Öğe Determination of Elastic Constants of Epoxy Resin/Biochar Composites by Ultrasonic Pulse Echo Overlap Method(Wiley, 2016) Oral, ImranThis study is carried out in order to determine the elastic properties of Epoxy Resin (ER) Composites reinforced with various mixtures of China Poplar Char (CPC) and Pine Cone Char (PCC) as biochars by ultrasonic wave velocity measurement method. The prepared chars are mixed with epoxy resin matrix at weight percentages of 10%, 20%, and 30% for preparing the ER/Biochars (BC) composites. The effect of biochar amounts on the elastic properties of the ER/BC composites are investigated by ultrasonic pulse echo overlap method. The morphologies of the samples are investigated by scanning electron microscopy. Based on the findings obtained from the present study, forming of the ER/CPC composites gives better values of elastic properties compared to forming of the ER/PCC composites. According to the obtained results, the composition ratio of 70:30 is the most appropriate composition ratio for both of the ER/CPC and the ER/PCC composites. (C) 2015 Society of Plastics EngineersÖğe Determination of mechanical and damping properties of hazelnut shell powder reinforced biocomposites by ultrasonic method(Wiley, 2023) Oral, Imran; Kocaman, Suheyla; Cerit, Alaaddin; Ahmetli, GulnareThis research was carried out to figure out the effect of chemical treatments of hazelnut shell powders (HSPs) on the elastic properties, ultrasonic wave velocities, and damping properties of bio-based epoxy resin (BER) biocomposites. Natural hazelnut shells (HSs) were chemically treated using sodium hydroxide (NaOH), and acetic anhydride (AA). Then, HSs that were chemically treated with NaOH and AA, and HSs that were not subjected to chemical treatment were ground to obtain HSPs. The treated HSPs (HSP-NaOH and HSP-AA), and untreated HSPs were contributed to the neat BER in varied compositions such as 10-50 wt% to obtain the BER/HSP, BER/HSP-NaOH, and BER/HSP-AA biocomposites. The effect of untreated, and treated HSP ratios on the density, ultrasonic wave velocities, Young's modulus, Bulk modulus, Shear modulus, Poisson ratio, microhardness, and damping characteristics (attenuation coefficient, loss tangent and quality factor) of the novel HSP-based biocomposites, was investigated by the ultrasonic pulse-echo overlap method (PEOM). A significant increase in the density, ultrasonic wave velocities, and elastic modulus values of the biocomposites was seen compared to the neat BER. Based on the obtained elastic modulus values, the most appropriate combination ratio between the neat BER, and HSP-NaOH was determined as 50:50.Öğe DETERMINING THE ELASTIC PROPERTIES OF EPOXY/SEMICONDUCTIVE GLASS COMPOSITES BY ULTRASONIC METHOD(Amer Inst Physics, 2014) Oral, Imran; Soydal, UlkuThe purpose of this study is to investigate the effects of the type and amount of semiconductive fillers on the elastic properties of epoxy (ER) / semiconductive glass (SG) composites by ultrasonic velocity measurments. Different semiconducting glasses (SG) binary systems such as As2S3-TlS and As2Se3-TlS were synthesized. ER/SG composites were formed 15 wt. % of fillers and characterized by ultrasonic velocity measurments. The ultrasonic wave velocities of composites were measured with the pulse-echo method at room temperature by a flaw detector. The values of the acoustic impedance, Poisson's ratio, and elasticity constants of the samples were calculated by the measured values of both longitudinal and shear ultrasonic wave velocities. According to the results, The highest elastic properties values were found in the ER/SG-3 composite using 50% As2Se3-50% TlS.Öğe Measurement of the elastic properties of epoxy resin/polyvinyl alcohol nanocomposites by ultrasonic wave velocities(Budapest Univ Technol & Econ, 2022) Oral, Imran; Ekrem, MurselThe polyvinyl alcohol (PVA) nanofiber mats are produced using the electrospinning method. The epoxy resin (ER)/polyvinyl alcohol (PVA) nanocomposites are obtained by adding PVA nanofiber mats into neat epoxy resin (ER) as 5, 10, and 15 layers. The elastic properties (elastic constants, Young's modulus, Poisson's ratio, and Shear modulus) of the neat ER, and the ER/PVA nanocomposites, are determined by ultrasonic longitudinal wave velocity (V-L) and shear wave velocity (V-S) measurements. The morphology of the neat ER and the ER/PVA nanocomposites is investigated using scanning electron microscopy (SEM). The results obtained from SEM images showed the ER/PVA nanocomposites have a transversely isotropic structure. The V-L value of isotropic neat ER was obtained higher than the value of V-L33 and V-L45 degrees but lower in x(1) direction for V-L11 in the ER/PVA nanocomposites. The velocity values of ultrasonic shear waves propagated in x(1) direction and polarized in y(2) direction in the ER/PVA nanocomposites are determined as higher than the velocity values of ultrasonic shear waves propagated in z(3) and polarized in x(1) direction. Also, the value of E-3 determined in the z(3) direction is found to be significantly higher than the value of E-1 determined in the x(1) direction when the number of PVA layers increased in the ER matrix. The value of shear modulus (G(31)) is found as 1.53, 1.76, and 1.61 GPa for the ER/PVA-5, the ER/PVA-10, and the ER/PVA-15, respectively. The Poisson's ratio values of the ER/PVA nanocomposites are determined as between 0.473-0.502 and 0.247-0.276 for mu(11) and mu(31), respectively. On the other hand, the degree of anisotropy in the ER/PVA nanocomposites is determined using ratios of E-1/E-3 and mu(11)/mu(31). A small degree of anisotropy in dynamic Young's modulus (0.93-0.99) is observed, while a higher ratio is observed for Poisson's ratio (1.71-2.03) with increasing PVA layers in neat ER.Öğe Preparation and ultrasonic characterization of modified epoxy resin/coconut shell powder biocomposites(Wiley, 2022) Oral, Imran; Kocaman, Suheyla; Ahmetli, GulnareA new bio-based epoxy resin (BER) is produced by the esterification reaction between sebacic acid (SAc) as bio-based acid and epichlorohydrin (ECH). The epoxy resin (ER) is modified with the BER. The biocomposites are prepared using untreated coconut shell powder (CSP), modified coconut shell powder (MCSP), and MER. The CSP and MCSP particles are mixed with MER in varied compositions (10-50 wt%) for preparation of the MER/CSP and MER/MCSP biocomposites. The influences of CSP and MCSP bio-fillers amounts on the physical properties (density, elastic constants, acoustic impedance, ultrasonic micro-hardness, and attenuation coefficient) of biocomposites are investigated using the ultrasonic pulse-echo overlap method (PEOM). It was seen that the densities, both ultrasonic longitudinal and shear waves' velocity values of obtained biocomposites were higher than those of the MER. All elastic moduli of the MER/MCSP biocomposites have higher values than of the neat MER and MER/CSP biocomposites.Öğe Ultrasonic Characterisation of Epoxy Resin/Polyethylene Terephthalate (PET) Char Powder Composites(Kaunas Univ Tech, 2016) Oral, Imran; Ahmetli, GulnareThis study is carried out in order to determine the elastic properties of the Epoxy Resin (ER) / Polyethylene terephthalate (PET) Char Powder Composites by ultrasonic wave velocity measurement method. Plastic waste was recycled as raw material for the preparation of epoxy composite materials. The supplied chars were mixed with epoxy resin matrix at weight percentages of 10 %, 20 % and 30 % for preparing ER/PET Char Powder (PCP) composites. The effect of PET char powder on the elastic properties of ER/PCP composites were investigated by ultrasonic pulse-echo method. According to the obtained results, the composition ratio of 80: 20 is the most appropriate composition ratio, which gave the highest elastic constants values for ER/PCP composites. On the other hand, the best electrical conductivity value was obtained for 70: 30 composition ratio. It was observed that ultrasonic shear wave velocity correlated more perfectly than any other parameters with hardness.Öğe Ultrasonic characterization of andesite waste-reinforced composites(Springer, 2017) Oral, Imran; Soydal, Ulku; Bentahar, MouradThe epoxy resin used in this study is modified with 5 wt% of polyaniline. Then electrically conductive modified epoxy resin (MER) (as matrix) and different weight amounts (10-30 wt%) of andesite waste (AW) as filler are mixed together to obtain the andesite waste-reinforced epoxy resin composites. The effects of filler amount on the electrical and ultrasonic properties of the modified epoxy resin are examined. The effects of AW amount on the ultrasonic properties of the obtained MER/AW composites are investigated by ultrasonic pulse-echo method. The conductivity of the composites is measured by a four-point probe (FPP) method, and the morphologies of the samples are investigated by scanning electron microscopy (SEM). Experimental results show that increasing the amount of AW causes a linear increase in the elastic properties. On the other hand, the same amounts of AW decrease the electrical conductivity of MER.Öğe Ultrasonic characterization of conductive epoxy resin/polyaniline composites(Wiley, 2015) Oral, ImranThis study presents the ultrasonic characterization of conductive epoxy resin (ER)/polyaniline (PANI) composites. The prepared PANI is mixed with ER matrix at weight percentages of 5%, 10%, and 15% for preparing the ER/PANI composites. The effects of PANI amount on the mechanical properties of ER/PANI composites are investigated by ultrasonic pulse-echo-overlap method. Also, electrical conductivity, ultrasonic wave velocity and ultrasonic micro-hardness values of ER/PANI composites are correlated. Experimental results show that there is an excellent correlation between ultrasonic micro-hardness and ultrasonic shear wave velocity. Also, the results of ultrasonic velocities and elastic constants values illustrate that the appropriate combination ratio is 95 : 5 for ER and PANI in ER/PANI composites. (c) 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 42748.Öğe Ultrasonic Properties of Epoxy Resin/Marble Waste Powder Composites(Wiley, 2015) Oral, ImranNon-destructive techniques are suitable alternatives for characterization of composites. The aim of this study is to analyze the composites of epoxy resin (ER)/marble waste powder (MWP) by ultrasonic method. The effects of marble powder, coagulant type, and dosage on the ultrasonic properties of ER/MWP composites were investigated. The ultrasonic wave velocities of composites were measured with the pulse-echo method at room temperature by a flaw detector. The values of the acoustic impedance, Poisson's ratio, and elastic constants of the samples were calculated by the measured values of the densities and both longitudinal and shear ultrasonic wave velocities. According to the results, the ER/MWP composite using sepiolite coagulant in dosages of 4 g/500 mL has showed the highest values of elastic constants. POLYM. COMPOS. 36:584-590, 2015. (c) 2014 Society of Plastics Engineers
