| Calcium phosphate (CP) biomaterials such as hydroxyapatite (HA) and tricalcium phosphate (TCP) has been studied widely by scholars and is a kind of appreciative biomedical materials used for bone prostheses by clinic doctors because it is similar to bones and teeth in inorganic compositions, has good biocompatibility and can bring chemical bonding with bone. Calcium phosphate powders used for medicine can be synthesized by chemical wet method or chemical dry method (calcining at high temperature). It is difficult to obtain calcium phosphate ceramics having high mechanical properties by using powders synthesized through traditional methods, so new methods of preparing and activating are required.Shock wave technology, as a study method of materials preparation and activating, possesses an important station in the area of materials study because this method can provide high pressure, high temperature and short time of reaction. There are more crystal lattice defects, the grain of powders will become more uniform, surface energy will increase obviously and chemical activation will increase after treating condensed matter's powders by shock wave. It results in improving the sintering characteristics and reaction activation. According to the theory mentioned, we decided to use shock wave to synthesize and activate (or modify) HA and TCP powders, the studies have not been yet reported in the world.HA powders were prepared by shock wave treatment method using the mixture of CaCO3 and CaHPO4-2H2O as raw materials in the present thesis. Structure and components of the prepared HA powders were characterized by XRD, SEM, and FT-IR. It has been shown that, comparing with HA powders prepared by calcining method, HA powders prepared by shock wave treatment method are similar to themin structure and components; have CO3 2- ions; are smaller and uniform grain size; are closer to bone crystals in XRD data, which is advantageous to the use in bone prostheses; have much higher activity because of the existing of strain and dislocation defects of crystals. It is believed that the method of shock wave treatment may be a new process for preparing HA powders as a useful kind of biomaterials.The activating and sintering characteristics of HA agglomerate treated by shock wave have been studied in the present thesis. The grain size refinement, homogenization and lattice deformation in shocked HA powders analyzed by XRD and SEM can promote sintering HA ceramics. The energy stored in shocked powders is released during sintering process. Form the study result of sintering dynamics of HA powders it is shown that there is lower sintering energy in shocked HA powders than that of unshocked HA powders. The temperature of maximum shrink rate of shocked sample reduces about 70℃ lower than that of unshocked one. The strength and density of HA ceramics made of the shocked sample can be obviously enhanced. HA ceramics having high strength used for artificial bone materials can be made with method used in the present study. The dissoluble properties of two kinds of ceramics made from the shocked- and unshocked-treatment HA powders were compared in the present thesis. Weight changes of HA ceramics from the shocked HA powders after immersing in simulated body fluid (SBF) are smaller, Ca2+ concentrations and PH values changes of SBF are also smaller than those of HA ceramics from the unshocked HA powders. The HA ceramics from the unshocked HA powders are more stable in the SBF.The study on preparing HA powders by hydrothermal process has been carried out in the present thesis. CaCO3 and CaHPO4.2H20 were added into an autoclave. The reaction carried out at various temperatures and for different time. The particle size of HA crystals was observed to be very fine, uniform, and less than 100nm. X-ray diffraction (XRD), Scanning electronic microscopy (SEM) and Fouier transform infrared spectroscopy (FTIR) were used to characterizing the morphology, structure, crystallite size and chemical composition of HA. From experimentalresults i...
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