| Calcium phosphate ceramics are widely used as bone replacements in the field of oral and orthopaedic surgery. As a kind of material having excellent physical chemistry performance, the porous P -tricalcium phosphate ( P -TCP) ceramic has good biocompatibility and biodegradable capability. This material can induce production of new bone and play an important role of osteophony to repair bone defects, hence it is an ideal bone transplanting material. However, the present preparing methods of the porous P -TCP bioceramics have many disadvantages. Gelcasting is a novel method of forming ceramics and has been increasingly employed in preparing complex-shaped, near-net-shape advanced materials. In order to get a more effective preparing technology of porous ceramics, porous P -TCP ceramics was fabricated by incorporation of forming pore agents method and gelcasting method in the paper.For the optimal quantity of gel factors, through careful comparing with the time of forming gel and the strength of the green gel body we got as follow proportion: AM was 5g, MB AM was 0.3g. the distilled water was 25ml, initiator which concentration was 15wt% was 0.6ml, catalyst which concentration was lwt% was 0.8ml, the temperature was 50 C. In this proportion, the time of forming gel was from 8 to 10 minutes. The compressive strength of the green gel bodies was about 5000 Pa, the dry shrinkage rate was about 50%, and the green bodies didn't fractured.In the paper, preparation of a concentrated suspension with low viscosity and high solid volume content and stability is the key to success in gelcasting technology. The results of the experiment indicated that the particles of -TCP/BG ceramics had perfect dispersing performance when pH valve was 10 and the dispersant was added. We studied the rheology of suspension of -TCP/BG ceramic powder with low viscosity and high solid content. We found that the factors of quantity of the dispersant, pH value of the solution, the content of the monomer and the cross-linking monomer, added in BG, the milling times, the solid volume content etc. played an important role to viscosity of the suspension. In the end, the suspension with solid volume loading 58vol% was suitable for need of gelcasting technology.The research results indicated that the dry shrinkage of -TCP/BG green body was inverse proportion with solid volume loading of the suspension. And the forming pore agents had influence on the dry shrinkage and the sintering shrinkage. By mean of analysis of the TG-DSC of -TCP/BG green body, the appropriate sintering technology could be fixed on . It was an important directive signification to improve finished product rate. Through analysis the appearance of the porous ceramics by SEM, we made sure that the porous P -TCP/BG ceramics had good pore structure .When solid volume loading of the suspension was 67vol% and the forming pore agents was 30wt% compressive strength of the green body of β -TCP/BG was l.5MPa. And compressive strength of the sintered porous P-TCP/BG bioceramics was 2.135MPa, average porosity of the porous ceramics was 75.45%, the average density was 0.6861g/cm , the infiltration was 15.90 10-3cm2-Pa, etc. The above results indicated that the incorporation technology of of forming pore agents method and gelcasting method was an effective method to prepare porous β -TCP/BG bioceramics.
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