TY - JOUR A1 - Yahya, Ahmed A1 - Mounir, Ahmed A1 - Al-Motori, Shirin A1 - Moustafa, Ahmed A1 - Kohail, Mohamed A1 - Raab, Bastian A1 - Soltan, AbdelMonem A1 - Mohsen, Alaa T1 - Investigation of the mechanical, microstructure, thermal and gamma-ray attenuation characteristics of serpentinite and ilmenite-based concrete as bio-shielding materials JF - Materials Today Communications N2 - Owing to nuclear technology’s significance in medical, industrial and military applications, this study assessed the effectiveness of some Egyptian raw materials in the production of heavy-weight concrete to shield hazards emitted radiations. Three mix-designs containing different coarser aggregates (dolomite (D), serpentinite (S) and ilmenite (Il)) were prepared. Their workability and physico-mechanical characteristics were examined. The hydrated concretes’ phase composition and microstructure were analyzed using XRD, TGA/DTG and SEM/optical-microscopy. The impact of elevated temperatures (300, 600 and 900◦C for 2 hrs) on the mechanical properties was studied. The volume stability of concrete specimens was investigated using a hot-stage microscope and thermodynamics calculations. Finally, the gamma-ray attenuation was evaluated against the 137Cs radioactive isotope with 0.662 MeV energy. The results revealed that Il-concrete has the highest slump value, highest bulk density and lowest water absorption. Also, it has the most outstanding efficiency in gamma-ray shielding; its attenuation is higher than D-concrete and S-concrete by 271.2 and 168.1 %, respectively. Replacing dolomite with serpentinite and ilmenite harms mechanical performance. However, the compressive-strength of the prepared concretes is in the range of 24.10–41.06 MPa at 28-days, achieving the building code’s requirements for structural concrete. At elevated temperature, S-concrete showed the highest compressive-strength retention and highest volume stability. Y1 - 2025 U6 - https://doi.org/10.1016/j.mtcomm.2025.113107 SN - 2352-4928 VL - 47 PB - Elsevier BV ER -