Properties |
Natural Diamond |
CVD Diamond |
DLC |
TetraBond |
Hardness |
100 |
80-100 |
11-50 |
80-100 |
Density |
3.5 |
3.2-3.4 |
1.7-2.2 |
3.0-3.2 |
Friction Coefficient |
0.1 |
.1 (Polished) |
< .1 |
<.1 (50% Humidity) |
Film Roughness |
--- |
--- |
Optically Smooth |
Optically Smooth |
Adherence to Substrate |
--- |
Low |
Moderate |
High |
Processing Temperature |
--- |
>600 C |
20-325 C |
20-150 C |
Structure |
Crystalline |
Crystalline |
Amorphous |
Amorphous |
Reactive Gas |
--- |
Yes |
Yes |
None Gas-Optional |
Tetrahedral amorphous carbon bridges the gap between CVD diamond
films and DLC films. Note in the table that the amorphous carbon coating has harnesses,
densities and coefficient of friction comparable to diamond films. Because it is amorphous
in structure, it requires no post coat polishing, compared to diamond films. Because it is
a carbon-carbon-bonded film, its non-hydrogenated character makes it more stable at
elevated temperatures and humidity than DLC films, which re carbon-based hydrogen films.
| Circuit Board Drilling Results Granted by Permission from Tycom/IBM |
|
|
TetraBond Contribution |
|
Low Coefficient of Friction |
|
High Hardness |
|
|
Results |
|
Improved Productivity of 25% |
|
Improved Tool Life Up to 5x |
|
Reduced Total Cost of Drilling of 25% |
Commercial Successes and Field Results
The application of amorphous carbon films to microdrills has been a technical and
commercial success. The tables on this page highlight some of the benefits realized by the
customer. A more thorough description of this success can be found in the March 1996 issue
of Printed Circuit Fabrication magazine.
The table below illustrates the types of materials and tool types
that have been coated.
Materials & Tool Types |
Materials |
Tool Types |
Aircraft Aluminum - 6000 and 7000 Series |
Drills - HSS and Carbide |
Automotive Aluminum - 308 through 390 |
End Mills - HSS and Carbide |
| Graphite |
Specialty Carbide Inserts and Milling Inserts |
Carbon/Carbon |
Form Tools |
Nylon |
Taps - Form and Cutting |
Brake Linings |
Reamers |
Plastics - Various |
|
Green Ceramics |
|
Natural Wood |
|
Composite Wood |
|
The table below illustrates field reports.
TetraBond Performance |
Tool Type |
Material Type |
Increased Life |
Comments |
Carbide Drills |
RF 38 Brake Lining |
4x |
Uncoated |
High Speed End Mills |
RF 38 Brake Lining |
9x |
4.5 x TiN |
High Speed Center Drills |
RF 38 Brake Lining |
36x |
Uncoated |
Carbide Drills |
G-10 Fiber Glass |
40x |
Uncoated |
Carbide Microdrills |
Circuit Boards |
5x |
Uncoated |
High Speed End Mills |
Graphite |
3x |
TiN |
Carbide Drills |
Aluminum -10% Silicone |
3x |
Uncoated |
Ceramic Inserts |
Aluminum -10% Silicone |
2x |
Uncoated |
Carbide Drills |
Aluminum -18% Silicone |
16x |
Uncoated |
Carbide Reamers |
Aluminum -16% Silicone |
30% |
TiCN |
Carbide Inserts |
Aluminum - 606IT |
3x |
Cut Cycle Time 50% |
Carbide Inserts |
Cast Iron |
6x |
Uncoated |
Carbide Ball Nose End Mills |
P-20 Mold Steel |
Same |
50% Increase RPM & 25% in Feed Over TiAlN |
This coating is especially good for drilling and reaming of cast
aluminums, milling and drilling of aircraft aluminum. Considerable success has also been
demonstrated in the milling of graphite.
Beginnings