Fabrication of Al2O3-Ni graded composites by centrifugal casting in an ultracentrifuge
Justyna Zygmuntowicz, Dominika Zielant, Przemysław Suchecki, Katarzyna Konopka, Waldemar Kaszuwara
Quarterly No. 3, 2018 pages 174-179
DOI:
keywords: ultracentrifuge, ceramic-metal composites, Functionally Graded Material (FGM), Al2O3-Ni
abstract The work explored the possibility of producing Al2O3-Ni gradient composites using non-absorbent molds in a high-speed centrifuge. As a result of the centrifugal force, the mass was compacted and the solvent was separated from the solid part. The influence of rotational speed and the change in the solid phase content in the slurry on the obtained microstructure of the composites was investigated. The produced composites were characterized on the basis of macroscopic observations of the obtained samples immediately after the casting process (green body) and after the sintering process. To determine the gradient of the metallic phase, the observations were made on cross sections of the samples. Densification of the sinters was determined by the Archimedes method. The obtained results showed that using an appropriate correlation of technological parameters, i.e. rotational speed and solid phase content in the slurry, enables the fabrication of Al2O3-Ni composites with a microstructure gradient by the centrifugal casting method using non-absorbent forms. It was found that with an increase in the solid phase content in the mass, a clear boundary is formed which separates the area containing only ceramic (Al2O3) and metallic (Ni) particles.