| Porousp-tricalcium phosphate(β-TCP)ceramics have many importantbiomedical applications,such as bone defect fillers,tissue engineering scaffolds anddrug delivery systems.At present,there are many ways to prepare porousp-TCPceramics,and the products prepared in different ways have different performance.Inthis paper,a new fabrication method was introduced to prepare porousβ-TCP cermics.Porousβ-TCP bioceramic was made by calcined amylum in high temperature, which use amylum nature of irreversible expansion after amylum hydrophilic and adhesive action after expansion.Diameter of amylum lie on different crop,pore forming material was made by using different diameter of amylun gradation,such this the size of hole was easyly controled by this method.Porousity was mainly effect by the adding of amylun proportion,the shape of goods was controled by the shape of mould,which using grouting method molding.During the time of geting rid of amylum adopt slowly heating-up and thermal insulation,taking thermal insulation in core formation and crystallization temperature,in this way the amylum could be completely removed and the intensity of material could be increased.The preparing process is followingβ-TCP powder and bioglass powder were mixed in weight ratio of 1:4.adding suitable proportional amylum,and mix sizing agent acrroding to solid-to-liquid radio.infunding the sizing agent to mould,taking process heating-up to control amylum expanding equably in room temperature to 85℃,to prevent the body destroy.the firing system as follows:room temperature to 85℃by 1h,and taking thermal 0.5h,to 337℃by 2h,taking thermal 2h,to 556℃by 1h,taking thermal 2h,to 870℃by 2h,and taking thermal 4h,and Last cooled in air.During the process,mixing the material equality and controling the solid-to-liquid radio are very important,this point not only was relation to the body's capability after drying,but also to the integrality of body and the equality of the distribution of hole.When reaching high temperature,the air should be inleted,to ensure the amylun be remove completely.By XRD analysis,it is found that theβ-TCP is a main crystal phase of the porous ceramics,and with a fewα-TCP and HA crystal phase.β-TCP powder and naphthalene was mixed in volume ratio.The ratio,size and shape of naphthalene will decide the porosity,pore size and pore shape of the final porous ceramics,and they also impacted strength of the ceramics.After the experiments,we got the following results(Each Data was the average of 5 specimens):with the ratio of 5%,10%,15 %,20%and 30%,the porosity was 38%,44%,62%,78%and 89%respectively, the compression strength was 37.18 MPa,5.24 MPa,4.20 MPa,3.41 Mpa and 0.86 MPa respectively.The products were also analyzed through SEM photographs and 3D imagines.There were abundant pores in the products with irregular shape and interconnected well,and the hole was intercomunication in three dimension.,but the thin qirder infect the compressing strength.In conclusion,using the method that making hole by amylun which was twopenny cost and the process easyly controled prepare porousβ-TCP bioceramic,it could get porousβ-TCP bioceramic which was intercomunication in three dimension,high porosity and suitable compressing strength.To sum up,the method has vast foreground in producing porous materials.
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