| Bone tissue engineering scaffold material is an important field of tissue engineering. It has been a hotspot that is studied by the scientists majoring in material and tissue engineering. The basic request of bone tissue engineering scaffold material is introduced, the biology derived material, biological ceramics, polymer material and composite are discussed, and their advantage and disadvantage and the development direction of them are analysed in this paper.Coral artificial bone is a kind of scaffold material that was applied in clinical practice early. But its degradation velocity is higher than that of the formulation of new bone, which limits the application of it. In this paper, the degradability of CaCO3 that is improved by bioglass is studied and the low temperature sintering of CaCO3 is realized.CaCOs decomposes at 846 ℃, which is gotten by experiment. The decomposition temperature gotten by thermodynamics calculation is 835℃, and it is shown that the decomposition temperature of CaCOa changes with the pressure of CO2 exponentially. So, it is not feasible in theory to realize solid state sintering of CaCO3 by rising the pressure of CO2. In the duration of the experiment, the relationship between the heat decomposition with the size of the particle, heating rate and the impurity is analysed by TG-DTA method, and the following laws has been drawn: the decomposition speed of CaCO3 is greatly influenced by the size of the particles and heating rate. The smaller size of the particles and the higher heating rate results in the higher decomposition velocity of the CaCO3. K and Na accelerate the decomposition of CaCO3 by forming eutectic with Ca.The degradation of the Ca-P bioglass in SBF is analysed by IR. A layer of Hydroxyapatite, which is like the mineral substance in normal bone tissues,forms on the Ca-P bioglass after being soaked in SBF. So it proves that the Ca-P bioglass has good biocompatibility.CaCO3 can dissolve into the bioglass and form amorphous substance through long-period interaction between them in high temperature environment, and the intensity of the material will descend with too long time of heat preservation. Below the decomposition temperature of CaCO3, the intensity of the material will ascend with the rising of sintering temperature. The intensity of the CaCO3-bioglass bi-phase ceramic is obviously higher than that of single-phase CaCO3 and bioglass. When the content of CaCO3 in the ceramic is up to 20%, the effect of particle reinforcement will be obvious and the intensity of the material reaches its Maximum. So the preferred sintering technology is fast sintering at low temperature, and its parameters are: the sintering temperature-750C; the holding time-20min.In this paper, with porosity and intensity as the targets, the influence of the aggregate particle size, the sintering temperature, the holding time, the content of the adhesives and the content of the pore former on the prosperity of the porous CaCO3 ceramic is studied. The porosity and flexural strength of the material decrease with the rising of the aggregate particle size; However, the porosity decreases and the flexural strength increases with the rising of the sintering temperature, the holding time and the content of the adhesives. But, the porosity decreases in a small scale when the holding time is prolonged, so it can be say that the influence of the holding time on the porosity is slight relatively. The porosity increases and the flexural strength decrease6s with higher content of pore former. It is gotten by comprehensive considering all the factors mentioned above that the best parameters of the technology are: the sintering temperature-750C; the holding time-20min; the content of bioglass-30%; the content of pore former-20%.
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