Plasma sprayed aluminum oxide coatings are commonly used for liners, heat exchangers, crucibles, and thermal heaters. Aluminum oxide nanotube (CNT) powder feedstock has been plasma sprayed to gain a nanocomposite coating with improved fracture toughness. It was observed during the process that the CNT-reinforced nanocomposites can be successfully synthesized through plasma spraying. A diagnostic sensor was used to develop a process map for plasma sprayed aluminum oxide nanotube nanocomposite coating. Field emission-scanning electron microscope was also used to analyze the images of the cross-sections plasma sprayed coatings. The properties of plasma sprayed coatings depends on degree of melting, impact and flattening of splat, CNT content, and its degree of dispersion in spray dried particles. Composite spray drying caused reduced thermal effect due to uniform CNT dispersion.
