Characterization of -TCP/alumina composite

Abstract

Calcium phosphate composite of -tricalcium phosphate ( -TCP) matrix with different amount of alumina (Al2O3) was studied. -TCP powder was initially prepared via mixing calcium carbonate and phosphoric acid to form precursor powder. In order to determine the optimum calcination temperature, three different temperatures (850!C, 950!C and 1050!C) were selected. XRD and SEM analysis were carried out to investigate changes in producing the -TCP powder. -TCP powder was mixed with alumina powder in four different compositions (1, 3, 5, 10 wt %) for 2 hours followed by drying, uniaxially pressing for pellet forming and sintering at 3 different temperatures i.e. 950!C, 1050!C and1100!C. Vickers microhardness test was used to determined hardness of dense structures. The optimum temperature was detected to be around 850!C. The addition of alumina and the increase of sintering temperatures have affected the hardness of - TCP composites. Sample with 10wt% of alumina and sintered at 1100!C shows the highest Vickers microhardness value (1.578 GPa). From FESEM, it is predicted that the hardness of sintered -TCP-alumina composite could be a strong function of the porosity volume fraction of the composite.