Biomedical Engineering Reference
In-Depth Information
wt% Fap
13.60
19.90 26.52
33.16 40.00
T (°C)
σ
r
(MPa)
1100
0.25
1.68
2.00
2.53
0.23
1150
0.50
2.11
2.20
2.73
0.54
1200
0.90
2.55
3.00
3.01
0.85
1250
1.36
2.86
3.80
6.23
1.33
1300
2.31
3.41
6.00
8.74
1.80
1320
3.80
6.10
8.00
9.80
4.50
1350
6.00
6.45
9.20
13.20
10.10
1400
7.10
7.10
9.60
13.70
11.80
1450
3.60
5.33
8.00
5.70
6.20
Green
0.10
0.20
0.20
0.30
0.20
Table 2. Rupture strength versus temperature of different TCP-Fap composites.
Fig. 3A shows the relative density and mechanical resistance of β-TCP - 13.26 wt% Fap
composites. The rupture strength and densification increase with sintering temperature. The
optimum densification was obtained at 1350°C (87%). The maximum mechanical resistance
reached 7.1MPa at 1400°C (Fig. 3A). This study shows that small additions of a Fap (13.26 wt
%) can significantly enhance the sinterability and strength of β-TCP.
The evolution of β-TCP - 19.90 wt% Fap composites of densification and mechanical
properties was practically similar to the β-TCP sintered with 13.26 wt% Fap (Fig. 3B). This
curve illustrates a maximum densification at about 89% corresponding to the composites
sintered at 1350°C. The mechanical resistance was similar to the β-TCP - 13.26 wt% Fap
composites in value and sintering temperature (7.1 MPa at 1400°C).
Fig. 3C illustrates the evolution of the composites densification relative to the temperature
between 1100°C and 1450°C. The densification was variable as a function of temperature.
Between 1100°C and 1200°C, the samples relatives' densities were very small for any
samples. An increase of density was shown between 1300°C and 1400°C, where the
optimum densities are about 89.1 % at 1350°C. Fig. 3C shows the mechanical properties of
the β-TCP - 26.52 wt% Fap composites samples according to the sintering temperature.
Between 1100°C and 1250°C, the rupture strength of TCP - 26.52 wt% Fap composites
samples was around 2-3 MPa. Above 1250°C, the rupture strength increases and reaches
maximum value at 1400°C (9.6 MPa). Above 1400°C, the mechanicals properties of
composites decrease during the sintering process. Indeed, the mechanical resistance of
TCP - 26.52 wt % Fap composites reaches the 8 MPa at 1450°C. The evolution of
mechanical properties of composites was considered a function of a sintering
temperature. At 1350°C, the mechanical resistance optimum of β-TCP sintered without
Fap additive reached 5.3 MPa (Bouslama et al., 2009), whereas the resistance increases to
9.4 MPa with 26.52 wt% Fap.
