Influence of Milling Parameters on the Characteristics of Alumina-Titania Nanocomposite Prepared by High-Energy Ball Milling

Abstract

High energy ball milling (HEBM) is a simple mechanical technique used for particle size reduction and mixing different materials from bulk to nanostructured materials. It is able to produce nano-size grains of ceramic-based composite and sometimes with sufficient energy new phase can be formed through the diffusion process. The present study focuses on the effect of HEBM on the structure, microstructure, and properties of alumina—titania (Al2O3-TiO2) nanocomposite. Elemental powders of Al2O3 and TiO2 were milled in a planetary ball mill at different milling times and milling speeds, then heated to 600 °C. The composites were characterized for phase identification, structural properties, morphology, and compaction behavior. The peak broadening was significant with increasing milling time. The unstable Al2TiO5 was formed at a lower milling time for 300 rpm but diminished after heat treatment. The lowest crystallite size was obtained after 10 h milling time and with the speed of 300 rpm which originated from grain refinement due to a large amount of defects generation during milling. Increasing milling time and milling speed influenced the green density as a result of fine composite particle size and TiO2 particles.