Calcium- titanate (CaTiO3) is a new bioceramic for its good mechanical properties and piezoelectrict effect. Calcium- titanate is a bioceramic used for femoral implacement to improve osteointegration. Better properties of nanosized materials in contrary to micrometer materials cause that biomedical experts used it to produce biomedicals. The goal of this research is to synthesize calcium- titanate powder with two methods, sol- gel and mechanical alloying and then to fabricate nanostructured balk calcium- titanate for biomedical applications. In the present study, two step sintering method has been applied to suppress the accelerated grain growth of nanostructured calcium- titanate in the last sintering stage. This method includes heating up to a higher temperature(T 1 ), cooling down to a lower temperature(T 2 ), holding for a instant time in this temperature(t 2 ). XRD, SEM, TEM and EDS applied to study the structure and morphology of calium- titanate powder and balk calcium- titantate. The changes of compressive strength, hardnees and fracture toughness of balk calcium- titanate under different regims of two step sintering were studied. Bioactive properties, cytotoxicity and cells adhesion of balk calcium- titanate produced by optimum regim were studied. It is concluded that to fabricate nanostructured balk calcium- titanate with destinsity of 96±0.5% theorical density(TD) and grain size of 5±1 nanometer T 1 must be 1250 ?C T 2 =1150 ?C and t 2 =10 (h). The results showed that balk calcium titanate fabricated by optimum regim of two step sintering has suitable bioactive and biocompatible properties. Keyword : nanostructured, bulk, calcium- titanate, two-step sintering.
