Fabrication and Characterization of HA-ZrO2-MWCNT Ceramic Composites

In this article, a new kind of hydroxyapatite-zirconia-carbon nanotube (HA-ZrO2-MWCNT) ceramic composites was fabricated to enhance the mechanical properties of a hydroxyapatite (HA) ceramic for satisfying various requirements in bone rehabilitation. A new dispersing process was proposed to ensure a homogeneous distribution of multi-wall carbon nanotubes (MWCNTs) in the HA ceramic matrix. The flexural strength and fracture toughness of the HA-ZrO2-CNT composites were enhanced by about 126% and 124%, respectively, as compared with those of the unmodified HA ceramics. The X-ay diffraction analysis revealed that a small quantity of HA decomposed in the composites with introduction of strengthening phases. The in vitro test results showed that the sample surfaces were covered with a new apatite layer after immersion in simulated body fluid for 10 days, indicating good biocompatibility of the composites.