Biomedical Engineering Reference
In-Depth Information
Filament
A
B
C
Bur
FIGURE 15.6
Schematic diagram of the bur situated
within the filament defining positions A, B,
and C on the bur.
2100
2025°C
25 mm
1900°C
C
A
1800
1700°C
B
Edge
Edge
Filament center
1500
0
5
10
15
20
25
Filament distance (mm)
FIGURE 15.7
Substrate temperatures as a function of filament dimensions.
It can be seen that regardless of the position within the filament the films are polycrystalline with
predominantly (111) faceted octahedral diamond. It is evident that the films are continuous, uniform,
and with good coverage. In addition, the grooves and the cutting edges were successfully covered
with the diamond coating. It is significant that the diamond morphology does not change significantly
between positions A, B, and C on the coated bur. However, the crystal size does vary with position.
The grain sizes are 8-10, 3-5, and 2-4 μm, for positions A, B, and C, respectively. The variation in
the average crystallite size along the length of the bur is most likely caused by the variation in sub-
strate temperature, with larger crystal sizes growing at higher substrate temperatures. Raman spectra
