Characterization of Al2O3-TiO2-eggshell nanocomposite prepared by high energy ball milling

This study aimed to enhance the properties of Al2O3 matrix composite, addressing issues such as low toughness, ductility, and instability for high-temperature applications. Titanium dioxide (TiO2) was chosen as a reinforcement due to its excellent chemical and mechanical stability, along with good compatibility with Al2O3. However, TiO2 still had drawbacks. Hence, the addition of eggshell was explored to understand its effect on the Al2O3-TiO2 nanocomposite. The Al2O3-TiO2-Eggshell nanocomposite was fabricated through a simple and cost-effective method, powder metallurgy. Eggshells were cleaned, dried in an oven for 24 hours, and ground into powder. Alumina (Al2O3), titania (TiO2), and eggshell powder (CaCO3) were milled in a planetary ball mill using 5 mm zirconia balls at 300 rpm for varying durations of 5, 10, 15, and 20 hours. Subsequently, the composition was characterized using X-Ray Diffraction (XRD), Scanning Electron Microscope (SEM), and Fourier-Transform Infrared Spectroscopy (FTIR). The XRD analysis revealed no detectable phases for Al2O3, TiO2, and CaCO3. However, after 20 hours of milling, TiO2 deposition covering the surface of CaCO3 was observed. The milled composite powder was analyzed using the Williamson Hall method to calculate crystallite size and internal strain. Longer milling times resulted in a more refined structure and increased internal strain in the ball-mounted Al2O3-TiO2-Eggshell composite. FTIR results exhibited the functional groups of the Al2O3-TiO2-Eggshell composite, with detectable changes at 300 rpm as milling time increased. This suggests a modification in the composite's chemical composition or structure. Overall, the study demonstrates the potential of eggshell inclusion in improving the properties of Al2O3-TiO2 nanocomposites, with implications for enhancing their suitability for high-temperature applications.