Yazar "Güler, Ömer" seçeneğine göre listele
Listeleniyor 1 - 13 / 13
Sayfa Başına Sonuç
Sıralama seçenekleri
Öğe A first-time fusion of TiNbWMoZrOx high entropy oxide (HEO) with zinc-tellurite glass: Toward superior physical properties(Elsevier B.V., 2024) Kılıç, Gökhan; Güler, Ömer; Kavaz, Esra; İlik, Erkan; Güler, Seval Hale; ALMisned, Ghada; Tekin, Hüseyin OzanWhile numerous oxide additives have traditionally been employed to enhance the radiation shielding capabilities of glasses, the unique attributes of high-entropy oxides (HEOs), a group of materials acclaimed in contemporary material science for their distinctive properties have remained unexamined in this specific area. This novel study explores the enhancement of radiation shielding properties in zinc-tellurite glasses through the integration of TiNbWMoZrOx High Entropy Oxides (HEO). Utilizing advanced synthesis techniques, including mechanical alloying and oxidation, the research successfully incorporates HEOs into glass matrices, aiming to improve gamma-ray and neutron attenuation. Characterization through X-ray diffraction (XRD), scanning electron microscopy (SEM), and X-ray photoelectron spectroscopy (XPS) confirms the uniform distribution and structural integrity of the HEOs within the glasses. The synthesis of glass samples with a base structure suitable for the molar composition of 25ZnO.75TeO2 (mol%) and glass samples doped with TiNbWMoZrOx (HEO) was carried out using the traditional high-temperature melting and annealing method. The outcomes demonstrate a concentration-dependent increase in shielding efficacy, particularly highlighting the superior performance of glasses doped with 4 mol% of TiNbWMoZrOx (HEC2–4), which exhibit significantly enhanced mass attenuation coefficients, lower half-value layers, and higher effective atomic numbers. This indicates the effective role of HEOs in boosting radiation protection capabilities. Comparative analysis with traditional shielding materials showcases the HEC2–4 glasses' competitive advantage, underlining their potential as a versatile shielding solution. It can be concluded that incorporating TiNbWMoZrOx high entropy oxides into zinc-tellurite glasses significantly augments their radiation shielding properties, offering a novel approach for enhancing protection against gamma-ray and neutron in various applications. © 2024 Elsevier B.V.Öğe Boron nitride nanosheet-reinforced WNiCoFeCr high-entropy alloys: the role of B4C on the structural, physical, mechanical, and radiological shielding properties(Springer Science and Business Media Deutschland GmbH, 2022) Kavaz, Esra; Gül, Ali Oktay; Başgöz, Öyküm; Güler, Ömer; Almisned, Ghada; Bahçeci, Ersin; Güler, Seval Hale; Tekin, Hüseyin OzanThe synthesis and extensive characterization of newly developed boron nitride nanosheet (BNNSs)-reinforced WNiCoFeCr high-entropy alloys (HEAs) are presented. The influence of B4C on the structural, physical, mechanical, and nuclear shielding characteristics of synthesized HEAs has been widely examined in terms of its monotonic effects on the behavior changes. The internal morphology and structural characteristics of the fabricated composites are first investigated using X-ray diffraction, scanning electron microscopy, and energy-dispersive spectroscopy. Wear testing is used to determine the coefficient of friction as a function of sliding distance. Experimental gamma ray and neutron setups are created to determine their shielding characteristics against nuclear radiation. Finally, the shielding characteristics of nuclear radiation for gamma ray and fast neutrons are compared extensively to those of many existing and new-generation shielding materials. Among the examined samples, the S2 sample with B4C and BNNSs reinforcement had the greatest mechanical characteristics. Our findings imply that increasing B4C directly contributes to the shielding qualities of nuclear radiation. The B4C created in the structure of BNNSs contributes to the overall properties of HEAs, which are crucial for nuclear applications, since HEAs are being examined as a component of future nuclear reactors. Additionally, B4C is a very versatile material that may be used in circumstances where mechanical and nuclear shielding properties need to be enhanced for a variety of radiation energies. © 2022, The Author(s), under exclusive licence to Springer-Verlag GmbH, DE part of Springer Nature.Öğe Boron nitride nanosheet-reinforced WNiCoFeCr high-entropy alloys: the role of B4C on the structural, physical, mechanical, and radiological shielding properties (vol 128, 694, 2022)(SPRINGER HEIDELBERG, 2022) Kavaz, Esra; Gül, Ali Oktay; Başgöz, Öyküm; Güler, Ömer; Almisned, Ghada; Bahçeci, Ersin; Güler, Seval Hale; Tekin, Hüseyin OzanNo Abstract Available.Öğe Development and in-depth experimental characterization of novel TiZrNbHfTaOx reinforced 316L stainless steel for advanced nuclear applications(Elsevier Ltd, 2024) Güler, Ömer; Albayrak, M. Gökhan; Başgöz, Öyküm; Tekin, Hüseyin OzanOxide Dispersion Strengthened (ODS) materials are known for their exceptional performance in high-temperature and radiation environments. This study explores the radiation shielding properties of 316L Stainless Steel reinforced with TiZrNbHfTaOx High-Entropy Oxide (HEO). By integrating HEOs into the 316L stainless steel matrix, we aim to enhance its structural and radiation shielding properties. The HEO was synthesized using high-energy ball milling and oxidation processes, followed by thorough characterization using X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy-dispersive spectroscopy (EDS). Our results indicate significant improvements in both gamma-ray and neutron shielding properties. The 316L SS samples reinforced with 20 % HEO exhibited the highest mass attenuation coefficients (MAC), lowest half-value layers (HVL), and highest effective atomic numbers (Zeff) across all tested photon energies. These enhancements are attributed to the high atomic number elements and unique synergistic effects of HEOs. Neutron shielding was evaluated through equivalent dose rate measurements, with the 20 % HEO sample demonstrating the highest absorbed dose rate percentage and superior neutron interaction cross-sections. Benchmarking against standard materials confirmed the superior performance of HEO-reinforced 316L SS, making it a promising candidate for advanced radiation shielding in nuclear reactors and other high-radiation environments. Our findings suggest that HEO reinforcement not only improves mechanical properties but also significantly enhances the radiation protection capabilities of 316L stainless steel. © 2024 Elsevier B.V.Öğe Enhanced radiation shielding via incorporating europium oxide in 316L stainless steel: Synthesis, physical, microstructural, shielding, and mechanical properties(Elsevier Editora Ltda, 2025) Tekin, Hüseyin Ozan; Yayla, Nihal; Albayrak, M.Gökhan; Güler, Ömer; Baykal, Duygu Şen; Alkarrani, Hessa; ALMisned, Ghada316L stainless steel is widely utilized in various industries due to its excellent corrosion resistance, mechanical strength, and biocompatibility, making it a preferred material for applications in nuclear filed. However, enhancing its radiation shielding and mechanical properties through reinforcement strategies, such as the addition of high-Z materials like Europium(III) oxide, is crucial for extending its functionality in high-radiation environments, where improved performance is essential for safety and durability. In this study, 316L stainless steel composites reinforced with varying amounts of Eu2O3 (1%, 5%, 10%, and 20%) were synthesized and investigated for their structural, mechanical, and radiation shielding properties. X-ray diffraction (XRD) analysis revealed that the face-centered cubic (FCC) structure of the steel matrix was preserved up to 5% Eu2O3 reinforcement, while higher concentrations led to phase formation and crystallographic changes. Scanning electron microscopy (SEM) and energy-dispersive X-ray (EDX) analysis showed uniform element distribution at low reinforcement levels, with particle clustering at 20% Eu2O3. Transmission factors (TFs) were evaluated using PHITS simulations for photon energies of 0.662 MeV, 1.1732 MeV, and 1.3325 MeV. The 20% Eu2O3 composite exhibited the lowest TF and highest attenuation properties, confirmed by mass and linear attenuation coefficients. Elastic modulus values decreased from 224.46 GPa in pure 316L to 189.26 GPa with 20% Eu2O3 reinforcement, reflecting the inverse relationship between mechanical stiffness and radiation shielding performance. Benchmarking against other shielding materials demonstrated superior performance of the Eu2O3-reinforced steel in gamma-ray attenuation. The 20% Eu2O3 composite shows strong potential for applications in nuclear radiation shielding where attenuation efficiency is prioritized over mechanical properties. © 2024 The AuthorsÖğe Examining the trade-off between structural, mechanical properties and shielding performance of Pr2O3-enhanced 316L stainless steel(Elsevier ltd, 2025) Yayla, Nihal; Albayrak, M.Gökhan; Güler, Ömer; Baykal, Duygu Şen; Alkarrani, Hessa; Almisned, Ghada; Zakaly, Hesham M.H.; Tekin, Hüseyin OzanThis study explores the structural, mechanical, and radiation shielding properties of 316L stainless steel composites reinforced with varying weight percentages of Pr2O3. The aim is to enhance radiation attenuation capabilities while maintaining structural integrity for nuclear applications. The composites were fabricated using the mechanical alloying method, followed by detailed characterization through X-ray diffraction, scanning electron microscopy, and energy-dispersive X-ray spectroscopy. Key radiation shielding parameters, including mass attenuation coefficient, linear attenuation coefficient, half-value layer, and effective atomic number, and transmission factor values were analysed using theoretical and computational models. Additionally, elastic modulus calculations were performed to assess mechanical properties. The results indicate that incorporating Pr2O3 significantly enhances shielding performance. The 316L-SS%20Pr2O3 composite exhibited the highest mass and linear attenuation coefficients values, with a notable reduction in half value layer values compared to the unreinforced 316L stainless steel. At lower photon energies, effective atomic number improved by 39.3 % for the 316L-SS%20Pr2O3 sample, while neutron shielding efficiency also increased. However, the elastic modulus decreased with higher Pr2O3 content, reflecting a trade-off between mechanical stiffness and radiation shielding efficiency. The findings demonstrate that 316L-SS%20Pr2O3 is a promising material for applications requiring superior radiation shielding, particularly in environments where mechanical load is secondary.Öğe Exploring the gamma-ray shielding performance of boron-rich high entropy alloys(Elsevier Ltd., 2025) Alan, Hatice Yılmaz; Güler, Ömer; Yılmaz, Ayberk; Susam, Lidya Amon; Kavaz, Esra; Kılıç, Gökhan; İlik, Erkan; Oktik, Şener; Akkuş, Baki; ALMisned, Ghada; Tekin, Hüseyin OzanHigh entropy alloys (HEAs) are innovative materials combining multiple principal elements, known for their exceptional properties and wide-ranging applications. This study assesses the gamma-ray shielding capacity of twelve boron-based HEAs through advanced computational methods. Key parameters in terms of understanding the material's ability to reduce radiation intensity, specifically half-value layer (HVL) and tenth-value layer (TVL); its capacity to absorb or scatter photons, including mass attenuation coefficient (MAC) and linear attenuation coefficient (LAC); and other related factors such as equivalent atomic number (Zeq), effective atomic number (Zeff), effective electron density (Neff), mean free path (MFP), and fast neutron removal cross-section (FNRCS) were calculated for photon energies between 0.015 and 15 MeV using the computational method Phy-X/PSD (Photon Shielding and Dosimetry). Additionally, the interaction of alpha particles and protons with these alloys was assessed by calculating energy deposition KERMA (Kinetic Energy Released per Unit Mass) and mass stopping power (MSP) using PAGEX (interaction of protons, alpha, gamma rays, electrons, and X-rays with matter) software, while SRIM (Stopping and Range of Ions in Matter) was employed to estimate particle penetration depths. Electron interactions were evaluated using ESTAR (Stopping Power and Range Tables for Electrons) for stopping power and penetration depth. Among the alloys, Sample 10, S10, (Zr10.8%-Hf21.3%-Nb11.0%-Ta21.6%-W22.0%-B13.1%) exhibited efficient shielding properties due to its high density and interaction characteristics. It can be concluded that boron-based HEAs with optimized compositions and high densities demonstrate significant potential for advanced radiation protection applications. © 2025 Elsevier LtdÖğe First exploration of Pr6O11 nanoparticle integration in borotellurite glasses: Synthesis, characterization, and performance for enhanced mechanical strength and radiation shielding(Elsevier ltd, 2025) Kılıç, G.; İlik, E.; Kavaz, E.; Durmuş, Hasan; Güler, Ömer; Birdoğan, Selçuk; Almisned, Ghada; Tekin, Hüseyin OzanThis study investigates the incorporation of Pr6O11 nanoparticles into lithium borotellurite glass matrices to enhance their mechanical and radiation shielding properties. Glass compositions, synthesized with varying Pr6O11 concentrations from 0 to 8 mol%, exhibited increasing densities from 4.00783 g cm−3 to 4.94440 g cm−3 and reduced molar volumes, confirming nanoparticle-induced densification. X-ray diffraction analysis revealed amorphous structures with shifts in the hollow band indicating compact network rearrangements. Scanning electron microscopy and energy-dispersive X-ray analyses confirmed homogeneous Pr distribution up to 6 mol%, with clustering observed in 8 mol% samples. Vickers’ microhardness values progressively increased, highlighting enhanced mechanical strength due to reduced non-bridging oxygen ions and network cross-linking. Gamma-ray shielding experiments demonstrated superior performance of the 8 mol% sample (Pr8), with the highest mass attenuation coefficients, effective atomic number, and reduced half-value layer. Neutron attenuation assessments further confirmed improved shielding capabilities, with Pr8 achieving the highest effective removal cross-section. In conclusion, Pr6O11-doped lithium borotellurite glasses demonstrate significant potential for advanced radiation shielding applications.Öğe First-ever fusion of high entropy alloy (HEA) with glass: Enhancing of critical properties of zinc-tellurite glass through TiZrNbHfTaOx incorporation(Elsevier Ltd, 2024) Güler, Ömer; Kılıç, Gökhan; Kavaz, E; İlik, Erkan; Güler, Seval Hale; ALMisned, Ghada; Tekin, Hüseyin OzanMany oxide additives have historically been used to enhance the radiation shielding properties of glasses, yet the potential of high-entropy oxides (HEOs), which have gained popularity in material science for their unique properties, has not been explored in this context. This study is the first to investigate the radiation shielding capabilities of Zinc-Tellurite glass infused with High Entropy Oxide (HEO), specifically utilizing the novel attributes of a synthesized TiZrNbHfTa. In this study, the nuclear shielding properties of newly fabricated Zinc-Tellurite glasses doped with TiZrNbHfTaOx with a composition (25ZnO·75TeO2)100-x. (TiZrNbHfTaOx)x (x = 0, 1, 2, 3, 4 mol%) were studied. Through the synthesis of a TiZrNbHfTa HEA and its integration into glass structure, we have developed a series of novel materials with enhanced protective properties against both gamma-ray and neutron radiation. Experimental results demonstrate that the HEO-infused glass, particularly the HEC1-4 composition, significantly surpasses traditional shielding materials in neutron attenuation, evidenced by its superior effective neutron removal cross-section. Additionally, the HEC1-4 glass demonstrates improved gamma-ray shielding capabilities, with increased mass attenuation coefficients and decreased half-value layers, indicating a higher capacity for photon interaction and absorption. It can be concluded that the incorporation of High Entropy Alloys into glass matrices not only opens a new frontier in radiation shielding materials but also provides a versatile and effective solution with considerable potential for enhancing safety measures in radiation-prone environments. © 2024 Elsevier Ltd and Techna Group S.r.l.Öğe Newly synthesized NiCoFeCrW High-Entropy Alloys (HEAs): Multiple impacts of B4C additive on structural, mechanical, and nuclear shielding properties(Elsevier, 2022) Gül, Ali Oktay; Kavaz, Esra; Başgöz, Öyküm; Güler, Ömer; Almisned, Ghada; Bahçeci, Ersin; Albayrak, M. Gökhan; Tekin, Hüseyin OzanHigh-Entropy Alloys (HEAs) are regarded as potential structural materials for fusion and next-generation fission reactors, which will be required to fulfil growing nuclear energy demands. In this study, a HEA-composite was synthesized by adding B4C to an HEA containing Ni. The microstructure of the obtained HEA-composite was examined and the changes in its mechanical properties were revealed. Additionally, the nuclear radiation shielding properties of the Ni-containing HEA, and the HEA-composite are investigated using experimental and theoretical methods. Our initial findings showed that with the addition of 2.5% B4C to the alloy, the hardness increased more than two times. The addition of B4C to the HEA matrix resulted in a more than 90% and a nearly twofold increase in compressive strength. The shielding qualities of gamma-ray and neutron radiation were investigated using experimental and theoretical approaches. Our findings demonstrated that increasing the B4C reinforcement considerably enhanced the composite material's neutron attenuation capabilities. On the other hand, no significant change in the gamma-ray shielding characteristics of HEA and HEA-composite samples was observed. The gamma-ray shielding characteristics of HEA and HEA-composite samples were compared to those of other alloy shields and commercial products. Our findings indicate that both HEA and HEA-composite samples exhibit superior gamma-ray shielding characteristics when compared to the control samples. It can be concluded that increasing B4C reinforcement may be a multifunctional tool in terms of improving the mechanical properties as well as neutron attenuation properties for advanced applications in nuclear radiation facilities and next-generation fission reactors. Additionally, due to their promising material features and higher gamma-ray shielding capabilities compared to other kinds of alloys and commercial shields, HEAs may be beneficial materials. © 2022 Elsevier LtdÖğe Phase Stability, Structural Properties, Electronegativity, Mechanical Properties, and Neutron and Gamma-Ray Attenuation Properties of Cantor High Entropy Alloys for Advanced Nuclear Applications(Springer, 2024) Tekin, Hüseyin Ozan; Güler, Ömer; Özkul, İskender; AlMisned, Ghada; Baykal, Duygu Şen; Alkarrani, Hessa; Kılıç, GökhanHigh Entropy Alloys (HEAs) hold considerable potential for sophisticated nuclear applications, offering a vast spectrum of compositional tuning to enhance mechanical properties at high temperatures, as well as to increase resistance to radiation and corrosion. This study explores the suitability of Cantor HEAs, specifically the CoCrFeMnNi matrix enriched with elements such as Zr, Nb, Mo, Hf, Ta, and W, for nuclear applications. These elements were selected for their high atomic numbers and neutron capture cross-sections, vital for enhancing gamma-ray and neutron shielding properties. Utilizing advanced computational and theoretical methods, the elastic modulus of these alloys was theoretically estimated while their radiation attenuation capabilities were evaluated through different Monte Carlo simulation codes. CoCrFeMnNiW demonstrated the highest elastic modulus (340.9 GPa), indicating significant mechanical robustness. The addition of W resulted in superior gamma-ray attenuation, with the lowest gamma-ray transmission factors and highest neutron shielding effectiveness among the studied alloys. The calculated mass attenuation coefficients and effective removal cross-sections values demonstrate the potential of these HEAs to provide effective radiation shielding. Our results showed a clear correlation between the elastic modulus and radiation attenuation properties, suggesting that mechanical stiffness does not compromise shielding capabilities. The comprehensive analysis of thermodynamic and structural parameters, including entropy of mixing, mixing enthalpy, and Valence Electron Concentration (VEC), provided essential insights into phase stability and microstructural characteristics. It can be concluded that CoCrFeMnNiW and its related Cantor HEAs as promising materials for advancing nuclear technology, offering a new horizon for safer and more efficient nuclear systems. © ASM International 2024.Öğe Synergistic effect of boron nitride and graphene nanosheets on behavioural attitudes of polyester matrix: Synthesis, experimental and Monte Carlo simulation studies(Elsevier Ltd, 2022) Başgöz, Öyküm; Güler, Seval Hale; Güler, Ömer; Canbay, Canan A.; Zakaly, Hesham M.H.; Issa, Shams A.M.; Almisned, Ghada; Tekin, Hüseyin OzanWe report the synergistic effects of boron nitride and graphene nanosheets on physical, structural, and nuclear radiation attenuation properties of polyester matrix-incorporated nanocomposites. Some critical material properties are thoroughly evaluated for several types of synthesized samples. Polyester is employed to strengthen graphene and boron nitride nanolayers, and their characteristics are investigated in detail. Additionally, we report the gamma-ray and fast neutron attenuation characteristics of synthesized nanocomposites to get a better understanding of the reinforcing effect as a function of material type and weight percentage. Thermal analysis findings indicate that adding graphene lowers the decomposition temperature but co-adding graphene and BNNS enhances thermal decomposition in comparison to graphene itself. Tensile tests showed that the inclusion of both GRP and GRP/BNNS strengthens the material. Among the polyester composite samples analyzed, the G3 sample with the most GNP reinforcement had the lowest HVL values throughout the broadest range of energy levels investigated. The recent findings may be beneficial to the scientific community in terms of incorporating these reinforcing types and ratios into polyester materials for a variety of applications, including industrial and research purposes. © 2022Öğe Synthesis and structural, electrical, optical, and gamma-ray attenuation properties of ZnO-multi-walled carbon nanotubes (MWCNT) composite separately incorporated with CdO, TiO2, and Fe2O3(Elsevier Ltd, 2022) Başgöz, Öyküm; Güler, Ömer; Evin, Ertan; Yavuz, Cağdaş; Almisned, Ghada; Issa, S.A.M.; Zakaly, Hesham M.H.; Tekin, Hüseyin OzanIn this study, Fe2O3, TiO2, and CdO semiconductor metal oxides were separately incorporated into the ZnO-MWCNT composite at different weight percentages. Accordingly, several experimental analyses on electrical, optical, and radiation shielding characteristics of coupled semiconductor metal oxides nanocomposites were performed to determine their monotonic impact on the investigated material properties. Moreover, gamma-ray shielding properties of these novel materials were determined using MCNPX general-purpose Monte Carlo code. At 5% oxide addition, the maximum electrical conductivity was found in all groups for all temperatures. Moreover, 5% oxide reinforcement resulted in the maximum reflection characteristics in all groups. Among the CdO doped materials, the CZnOCd5 sample exhibits the highest electrical conductivity behaviour at room and high temperatures. The Eg value calculated for the CZnOCd5 sample was 3.284 eV. The CZnOCd2.5 and CZnOCd5 samples had the greatest Eg values when compared to the pure sample and the samples from other groups. The CZnOCd5 sample has the highest reflectance value in the CZnOCd group's reflectance graph. On the other hand, the maximum gamma-ray attenuation properties were reported for CZnOCd5 sample. Among the analysed samples, the CZnOCd5 sample's characteristics provide a preliminary motivation for a more comprehensive analysis of this material and assessment of potential radiation protection applications. © 2022 Elsevier Ltd and Techna Group S.r.l.
