Fabrication Of HA-BOTE Bioceramic Material And Its Bioactivity

Porous hydroxyapatite [Ca₁₀?PO₄?₆?OH?₂, HA] ceramics have plenty of porosity, which is conducive to the occurrence of ion exchange with body fluids, and the promotion of the rapid growth of new bone. However, porous HA ceramics still have the same shortcomings such as poor mechanical properties and low intensity as other ceramics, thus had been limited its application in the fields of bioceramic material. In recent years, researchers have committed themselves to the study of improving mechanical properties of HA porous ceramics.In order to obtain the hydroxyapatite ?HA? composite coating with more excellent mechanical properties and bioactivity, the HA-SrCO₃-SiO₂, HA-SrCO₃-ZnO, HA-Fe₂O₃-ZnO and HA-SiO₂-ZnO composite coatings with binary osteogenesis trace element compounds ?BOTE? SrCO₃-SiO₂, SrCO₃-ZnO, Fe₂O₃-ZnO and SiO₂-ZnO were fabricated by electrophoretic deposition and sequential sintering treatment, meanwhile chitosan as pore-forming agent. The obtained composite coatings were tested and characterized by FTIR, Lloyd LR5K Plus Testing Instrument, SEM, EDS, XRD and CHI, respectively. The bioactivity of the HA-BOTE composite coating was evaluated by immersion in 1.5 times of ionic concentration of simulated body fluid ?1.5SBF?.The experimental results show that the bonding strength between HA-SrCO₃-SiO₂, HA-SrCCb-ZnO, HA-Fe₂O₃-ZnO and HA-SiCh-ZnO composite coating with substrate reach 28.8 MPa,27.0 MPa,28.7 MPa and 26.5 MPa, respectively. The surfaces of the composite coatings are completely carbonated hydroxyapatite after immersion in 1.5SBF for some days, which indicate that the obtained HA-BOTE composite coatings possess better bioactivity than that of pure HA coating. The performance of HA-SrCO₃-SiO₂ composite coating is the most excellent, it is expected to be the promising artificial bone replacement for the implant bioceramic material.