Gül, Ali Oktay; Gökhan Albayrak, M.; Güler, Ömer; Özkul, İskender; Baykal, Duygu Sen; Almisned, Ghada; Tekin, H.O.

This study addresses a fundamental materials design question for radiation-resistant superalloys: whether rare-earth (RE) oxides are more effective when incorporated individually or when introduced collectively in a high-entropy rare-earth oxide (HE-RE2O3) form. In this context, Inconel 718 (IN718) composites were reinforced with single RE2O3 phases such as Sm2O3, Tm2O3, Er2O3, Yb2O3, Eu2O3, and La2O3 at 10 wt% and with a mechanically alloyed HE-RE2O3 phase at 1-20 wt%. Structural analyses confirmed the formation of a single-phase HE-RE2O3 with a cubic bixbyite structure and its stable integration into the IN718 matrix. Gamma-ray shielding properties were systematically evaluated over a wide photon energy range. The HE-RE2O3 reinforced samples, particularly at higher loadings, exhibited consistently higher mass and linear attenuation coefficients, elevated effective atomic numbers, reduced half-value layers, and lower buildup factors compared to both the base alloy and single-oxide reinforced counterparts, demonstrating a clear collective attenuation effect. Fast neutron removal cross sections showed more moderate variations, reflecting the dominance of neutron scattering and mass-dependent interaction mechanisms rather than atomic number effects. It can be concluded that incorporating RE elements through a high-entropy oxide configuration provides a more effective and collective compositional contribution for enhancing the radiation shielding performance of IN718 than adding RE oxides individually, offering a promising pathway for advanced nuclear and radiation-relevant applications.

AtıfScopus1·OpenAlex1

İncele

ALMisned, Ghada; Yayla, Nihal; Albayrak, M.Gökhan; Güler, Ömer; Baykal, Duygu Sen; Alkarrani, Hessa; Tekin, H.O.

Four composite samples were fabricated, maintaining 10 % B4C and varying La2O3 content from 0 % to 20 %. X-ray Diffraction (XRD), Scanning Electron Microscopy (SEM), and Energy Dispersive X-ray Spectroscopy (EDX) analyses confirmed the successful incorporation of reinforcements, preserving the austenitic structure of 316L-SS. Elastic modulus calculations revealed a gradual reduction from 225.0 GPa to 215.0 GPa with increasing La2O3 due to clustering and reduced homogeneity. Gamma-ray shielding properties demonstrated significant improvements, particularly at low and intermediate photon energies, with Sample 4 with 20 % La2O3 addition, achieving a 13.6 % higher linear attenuation coefficients (LAC) at 0.015 MeV. Neutron shielding highlighted Sample 4 as one of the most effective materials, outperforming conventional alloys. This study demonstrates the potential of 316L Stainless-Steel (316L-SS) + B4C + La2O3 composites as multifunctional materials for radiation-intensive applications, offering superior attenuation and structural stability. It can be concluded that optimization of reinforcement distribution would play an important role in balancing mechanical and shielding performance in next-generation nuclear materials.

AtıfScopus5·OpenAlex5

İncele