Microhardness and microstructural properties of a mixture of hydroxyapatite and β-tricalcium phosphate

Figures & data

Figure 1. Thermogravimetric and differential thermal analyses (TG/DTA) of (a) CaCO₃ and (b) NH₄H₂PO_4.

Figure 2. XRD patterns of (a) HA and (b) β-TCP synthesized at different temperatures by the reaction of CaCO₃ and NH₄H₂PO_4.

Table 1. Calculated lattice parameters, unit cell volumes, and densities of HA and β-TCP.

Sample	Lattice parameters (Å)		Unit cell volume V (Å^3)	Density Dx (g/cm^−3)
	a	c
HA	9.41	6.87	526.83	3.11
β-TCP	10.43	37.39	3522.53	3.07

Figure 3. FE-SEM morphology of the (a,b) HA and (c,d) β-TCP powders synthesized at 1200 and 800°C, respectively.

Figure 4. (a) XRD patterns and (b) FT-IR spectra for different ratios of HA/β-TCP mixture (CPM).

Figure 5. EDX spectra of (a) HA and (b) β-TCP powders synthesized at 1200 and 800°C, respectively.

Table 2. Results of calculation of Ca/P ratio based on EDX analysis.

Sample	StoichiometricCa/P ratio	EDXCa/P ratio
HA	1.67	1.71
90 HA	1.65	1.68
70 HA	1.62	1.63
50 HA	1.58	1.60
30 HA	1.55	1.58
TCP	1.5	1.54

Figure 6. FE-SEM cross-sectional images of (a) HA, (b) 90 HA, (c) 70 HA, (d) 50 HA, (e) 30 HA, and (f) TCP sintered at 800°C for 2 h.

Figure 7. (a) Porosity and (b) pore size distribution depending on the surface microhardness of xHA-(100-x)β-TCP (x = 0, 30, 50, 70, 90, and 100) CPM.

Figure 8. Surface microhardness of xHA-(100-x)β-TCP (x = 0, 30, 50, 70, 90, and 100) CPM sintered at 800°C for 2 h.

Data availability statement

Data available on request from the authors.