Investigation of the effects of gamma radiation and Y2O3 on the elastic properties of Al2024 composites by ultrasonic method

Abstract

In this study, the effect of Y₂O₃ contribution and γ-irradiation on the elastic properties of pure Al2024 and Al2024/Y₂O₃ composites was precisely investigated with the help of determined density and ultrasonic wave velocities. Ultrasonic longitudinal and shear wave velocity measurements of the samples were performed at room temperature using the ultrasonic pulse-echo method at 20 and 5 MHz frequencies, respectively. X-ray diffraction analysis and scanning electron microscopy examined the microstructural properties and phase characterizations of metal matrix composite (MMC) samples. A gamma cell type ⁶⁰Co source was used to irradiate MMC samples in the air at room temperature. The absorbed dose rate was measured to be approximately 1.5 kGy/h, and the total delivered dose was 50 kGy. According to the findings obtained from the research, the contribution of Y₂O₃ to pure Al 2024 at 0.5, 1, and 5 wt% ratios and exposure to gamma rays of 50 kGy caused a decrease in V_L, L, K, and μ values and a significant increase in ρ, V_S, G, HV, H, and E values. The highest Young's modulus values compared with pure Al2024 were obtained in both unirradiated and irradiated Al2024/0.5Y₂O₃ composites.