Yazarlar

  • MakaleYalnız künye2025Scopus SJRQ2
    Exploring the gamma-ray shielding performance of boron-rich high entropy alloys

    Alan, Hatice Yilmaz; Guler, Omer; Yilmaz, Ayberk; Susam, Lidya Amon; Kavaz, Esra; Kilic, Gokhan; Ilik, Erkan; Oktik, Sener; Akkus, Baki; ALMisned, Ghada

    High 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.

    AtıfScopus12OpenAlex13
    ScopusWeb of Scienceİncele
  • MakaleYalnız künye2024Scopus SJRQ1
    Effect of oxidation on radiation shielding capacity of ZrNbTaMoW Refractory High Entropy Alloys (RHEA) for nuclear reactor applications: Experimental and theoretical assessment

    Sakar, E.; Guler, O.; Alim, B.; Guler, S.H.; Dikici, B.; Lampke, T.

    This study presents the production and comprehensive assessment of a Refractory High Entropy Alloy (RHEA) with a ZrNbTaMoW composition for possible usage nuclear reactor applications. The alloy was synthesized using the mechanical alloying (MA) method, and its radiation properties were examined. Elemental powders of Zr, Nb, Ta, Mo, and W were utilized in equimolar quantities during the 120-hour MA process, conducted under a high-purity Ar atmosphere to prevent oxidation. The obtained HEA was then subjected to a mechano-thermal process to transform it into Refractory High-Entropy Oxide (RHEO) for comparing their radiation-shielding performance under oxide conditions. The characterization of the produced alloys through X-ray diffraction (XRD), scanning electron microscopy (SEM), and electron dispersive spectroscopy (EDS). The photon shielding parameters of the alloys were experimentally obtained for various energies emitted from a 133Ba radioactive source, employing a Canberra UltraLEGe semiconductor detector. Furthermore, theoretical calculations were performed to validate the experimental data and to evaluate the alloys' photon shielding capabilities comprehensively. For this purpose, Phy-X/PSD software was employed to determine mass attenuation coefficients, half-value layer, effective atomic number, and effective electron density. Fast neutron absorption capabilities were determined through the calculation of average absorption cross-sections in the 2–12 MeV energy range. The results showed that the oxidation process significantly diminished the photon absorption capacity of RHEA.

    AtıfScopus34OpenAlex37
    ScopusWeb of Scienceİncele
  • MakaleAçık Erişim2023Scopus SJRQ1
    A comprehensive study on structural properties, photon and particle attenuation competence of CoNiFeCr-Ti/Al high entropy alloys (HEAs)

    Sakar, Erdem; Guler, Omer; Alım, Bünyamin; Say, Yakup; Dikici, Burak

    It is well known that high entropy alloys (HEAs) have a wide range of potential applications as radiation shielding due to their superior properties. The CoNiFeCr-Ti/Al compositions were chosen for their low cost as HEA in this study. The HEAs were successfully produced using the mechanical alloying (MA) method with equimolar CoNiFeCr, CoNiFeCrAl, and CoNiFeCrTi compositions. The production and structural properties of the alloys were investigated in detail. Besides, the photon and particle radiation shielding properties of the HEAs were calculated with the help of Phy-X/PSD, SRIM (10 keV-20 MeV), and ESTAR (10 keV-20 MeV) programs. The photon-matter interaction parameters were calculated in both specific photon energies emitted from 241Am, 133Ba, 109Cd, 60Co, 137Cs, 131I, and 22Na nuclides and a continuous energy range of 15 keV-15 MeV. The characterization of the alloys was investigated by using X-ray diffraction (XRD) and scanning electron microscopes (SEM) attached to an energy dispersive spectroscopy (EDX). It was found that the HEAs have a highly amorphous structure due to the selected production method. The crystal size of the alloys was calculated as 70, 35, and 20 nm for CoNiFeCr, CoNiFeCrAl, and CoNiFeCrTi, respectively. In terms of shielding properties, it has been determined that the produced HEAs have better shielding characteristics for photon and particle radiations than standard shielding concretes. In addition, the results demonstrated that CoNiFeCr alloy, which has the best shielding ability among the HEA alloys, can be used as a shielding material application requiring photon, electron, proton, alpha, and neutron radiations.

    AtıfScopus30WoS32OpenAlex32
    ScopusWeb of Scienceİncele
  • MakaleYalnız künye2020Scopus SJRQ1
    Evaluation of the radiation shielding capabilities of the Na2B4O7–SiO2–MoO3-Dy2O3 glass quaternary using Geant4 simulation code and Phy-X/PSD database

    Aşkın, A.

    The important gamma and neutron radiation shielding parameters of the Dy3+ doped (65-x)Na2B4O7–15SiO2–20MoO3-xDy2O3 (x = 0, 5, 10, 15, 20 mol%) glass quaternary system were investigated to provide decisive information for their application in radiation environment. Gamma and neutron attenuation properties of the glass systems studied here were evaluated in terms of the mass attenuation coefficient (μm), transmission fraction (TF), half value layer (HVL), mean free path (MFP), effective atomic number (Zeff), exposure buildup factors (EBF) and fast neutron removal cross-section (∑R) parameters. Investigation of the each aforementioned parameter was performed thanks to the utilization of Monte Carlo simulations along with the Phy-X/PSD database. The photon attenuation characteristics were evaluated for gamma ray energies varying between 0.284 and 5.0 MeV. This study indicated that increase of the Dy2O3 content from 0% to 20% mole, enhances the gamma shielding capability due to the increase of the parameters μm and Zeff. In this study it was also observed that ∑R increases from 0.099 to 0.107 cm−1 as the molar fraction of Dy2O3 increases.

    AtıfScopus75WoS74OpenAlex82
    ScopusWeb of Scienceİncele
  • MakaleYalnız künye2020Scopus SJRQ1
    Assesment of the gamma and neutron shielding capabilities of the boro-tellurite glass quaternary containing heavy metal oxide using Geant4 and Phy-X/PSD database

    Aşkın, A.

    This survey was conducted to reveal the gamma and neutron stopping performance of the 30PbO–10ZnO—(60-x)TeO2—xB2O3 (x = 0, 10, 20, 30, 50% mole) glass quaternary. Gamma and neutron attenuation parameters including the linear attenuation coefficient (μ), transmission fraction (TF), half value layer (HVL), mean free path (MFP), effective atomic number (Zeff), exposure buildup factor (EBF) and fast neutron removal cross-section (∑R) were determined computationally using the Geant4 and Phy-X/PSD database tools and for photon energies ranging between 0.284 MeV and 2.510 MeV. It was found that increasing the B2O3 content from 0% to 50% mole and correspondingly decreasing the TeO2 content from 60% to 10% mole results in a degradation of μ by 18.2% and of Zeff by 28.6% at 0.284 MeV. Due to this decrease in μ and Zeff, the values of TF and HVL increased by 37.3% and 22.4% respectively. In the present study it was also observed that the density (ρ) of glass quaternary decreased with the decreasing content of TeO2, and that the density of glass has a remarkable effect on the photon attenuation characteristics. The Degradation of μ, Zeff, ρ and the increase of TF and HVL proves that the photon attenuation ability of the glasses investigated worsens with decreasing content of TeO2, as Tellurium's atomic number and atomic mass are high compared to those of boron. While the decrease of TeO2 weakens the photon attenuation performance, it was found that fast neutron attenuation increases as ∑R increases from 0.108 to 0.116 for the glass specimens containing 60% and 10% mole of TeO2 respectively.

    AtıfScopus31WoS31OpenAlex33
    ScopusWeb of Scienceİncele