Preparation And Mechanical Properties Study Of α-tricalcium Phosphate Bone Cement

α-tricalcium phosphate bone cements are a bioactive graft material in the form of a powder and a liquid, Both phases after mixing can form a viscous paste that sets and hardens within the body.In this paper, The methods of preparing a-TCP were discussed from the perspective of synthetic materials and calcination process.After that,Ball milling was used to process a-TCP powder to study the effect of different ball milling time,Based on this,with a-TCP being the main component, both the solid additive including hydroxyapatite, calcium dihydrogen phosphate, calcium carbonate and the liquid additive including citric acid and glucose were investigated to study their effect on the setting time and mechanical properties. Results are as follows:Compared with the phase transition between (3-TCP and a-TCP, the solid phase reaction between calcium carbonate and calcium hydrogen phosphate is easier to obtain α-TCP.Besides, using a lower Mg content starting material is more readily available a-TCP; calcination temperature needs to be above 1300’C to obtain the a-TCP powder. Besides improving the calcination temperature can obtain a high-purity a-TCP. when calcination time is 2 hours, it is enough to obtain a higher content of a-TCP product, to extend the firing time has little effect on the final product composition; air-cooled, water-cooled or nitrogen cooling is enough to obtain a higher content of a-TCP product.With the extension of milling time a-TCP particle becomes smaller, as well as narrower range of distribution. Besides the particle morphology changes from rod into irregulars. When mixing a-TCP with 2.5wt.%Na2HPO4, with milling time increasing, the setting time first decreases and then increases, the compressive strength first increases and then decreases, and the minimum curing time is 4 min, the maximum compressive strength is 24.58MPa.When HA is added into the solid powder of a-TCP bone cement, with the addition amount increasing, the setting time first decreases and then increases, which is about 6 minutes at 5%; the compressive strength decreases, reaching 7MPa at 20%. When adding MCPM, with the addition amount increasing, both the setting time and the compressive strength decrease gradually, when addition amount is 10%, the setting time is only about 30 seconds and the compressive strength reaches 6MPa. When adding CaCO3, with addition amount increasing, the setting time has no significant change, the compressive strength increases, reaching 24MPa at 2% addition amount.When citric acid is added into the setting liquid, with addition amount increasing, the setting time gradually decreases, which is only 30 seconds at 20%, the compressive strength first increases and then decreases, which is 30MPa at 7%. When adding glucose, with addition amount increasing, both the setting time and the compressive strength gradually increase, when the addition amount is 20%, the setting time increases from 15 minutes to 25 minutes, the compressive strength increased from 15MPa to 23MPa.