The sintering of tricalcium phosphate

This article investigates the sintering of tricalcium phosphate obtained by solid state reaction, for elaboration of dense materials. The evolution of the sintered material density as a function to time and temperature has been followed. The tricalcium phosphate presents a good sinterability in the range 1200-1350 degrees C. Thus, a densification rate of about 92% was reached at 1300 degrees C. At temperature higher than 1350 degrees C, the densification was hindered by the grain growth and the formation of large pore. X-ray diffraction showed besides the tricalcium phosphate, the presence of a phase traces of tricalcium phosphate and the tetracalcium phosphate. The analysis by nuclear magnetic resonance of the solid P-31 illustrates the presence of three types of tetrahedral site. Differentially thermal analyse shows that two phase changes of the tricalcium phosphate occurred at 1285 and 1475 degrees C, respectively.