Structural, morphological and mechanical investigations of in situ synthesized c-CeO2/α-Al2O3 composites

The development of c-CeO2/α-Al2O3 composites targeted for load bearing orthopaedic applications was investigated. Three different c-CeO2/α-Al2O3 compositional ratios were synthesized in situ and the results were compared with pure forms of both c-CeO2 and α-Al2O3. The thermal stability of the c-CeO2/α-Al2O3 composites depend on the individual precursor ratios and the particle morphology of c-CeO2 intends to vary with respect to the Al2O3 content in the composites. The combined presence of Ce4+ and Ce3+ states leading to the formation of a super structured lattice was confirmed through TEM analysis. Ce3+ presence in c-CeO2 led to its lattice expansion and any kind of Al3+ occupancy at the c-CeO2 lattice was discarded from the present investigation. Moreover, the presence of excess c-CeO2 in c-CeO2/α-Al2O3 composites was found detrimental to the mechanical strength of the composites.