| Calcium silicate ceramic is a new ceramic with good biological properties discovered inrecent years and has the wide application prospects; however, the defects (such as difficulty insintering and poor mechanical property) of common calcium silicate ceramic imposerestrictions on the application of calcium silicate ceramic in bone transplantation, especially inload-bearing bone transplantation. In order to improve the mechanical property of calciumsilicate ceramic, the paper focuses on the preparation technology of nano-powder, thehot-pressing sintering process of ceramic and the biological property testing and evaluation ofceramic samples in later period from the perspectives of nanometer ceramic technology andhot-pressing sintering technology.The study takes calcium nitrate (CaNO3·6H2O) and tetraethoxysilane (Si(OC2H5)4) as rawmaterials, prepares nano calcium silicate powder with sol-gel method, and explores the effectof the heat treatment temperature and duration in preparation process on the power crystallinephase and the powder particle size. In addition, the study employs hot-pressing sinteringequipment to sinter the prepared powder, addresses the effect of the factors (such as sinteringtemperature, holding time, sintering pressure, etc.) during sintering process on ceramicproperties, carries out in vitro biological property test for the prepared ceramic samples, andinvestigates the inducibility of calcium silicate bio-ceramic to bone-like hydroxyapatite.The results show that different heat treatment temperatures and durations have greateffect on powder crystalline phase and shape, and the powder particles from heat treatmentare more even and of the short rod-like structure with diameter of30nm and length ofaround50nm when the dry gel powder is at890℃and the holding time lasts for1h. When thetemperature is950℃, the sintering pressure is35MP, and the holding time lasts for20min, thecalcium silicate ceramic with better mechanical properties is obtained, with the compressivestrength of241MP and Vickers hardness of660Hv. When carrying out in vitro activity forsamples, hydroxyapatite coating appears on the surface of samples after3days, whichindicates that the calcium silicate ceramic with high strength has good biological activity. |
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