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WELCOME TO DAV-TECH ALUMINUM HARDCOATING:
Hardcoating,
also called hard anodizing, is very similar to sulfuric acid
anodizing in that it is a coating of aluminum oxide that is produced
on the surface of an aluminum component in the presence of a
sulfuric acid electrolyte. Compared to sulfuric acid anodizing,
a hardcoating bath is usually run at lower temperatures, higher
amperages, and higher voltages. The resultant coating is far
superior to sulfuric acid or chromic acid anodizing in terms
of wear and corrosion resistance. These properties can be enhanced
by the use of sealants. Dav-Tech hardcoating can be processed
to meet the challenges of specific wear and corrosion applications.
BENEFITS
OF DAV-TECH ALUMINUM HARDCOATING:
- Abrasion
resistance
- Corrosion
resistance
- Erosion
resistance
- Low
coefficient of friction
- Flame
resistance
- Dielectric
properties
- Excellent
heat emissivity
- Safe
for food stuffs (cookware)
- Non-contaminating
to blood supplies (medical instrumentation)
- Ceramic-like
- Light-weight
- Applicable
to most aluminum alloys
PLANNING
FOR DAV-TECH HARDCOATING:
Since the anodic hardcoat layer is produced by converting the
surface aluminum into aluminum oxide, hardcoat is both a penetration
into the metallic surface as well as a buildup. Typically the
total thickness of the anodic coating is 50% penetration and
50% buildup. It is this penetration feature that renders the
coating integral with the substrate, and differentiates it from
other electrolytic coatings. It is this same feature the requires
the planning of critical dimensions on parts to be hardcoated.
For example, a 1.000" diameter shaft hardcoated .002"
will increase the 1.002" as a final diameter. That is a
buildup of only .001" per side. Similarly, a 1.000"
bore will decrease to .998".
The
typical hardcoating thickness of .002" - .004" can
be controlled to close tolerances, and can be finished by precise
abrasive methods to meet extremely fine dimensional requirements.
Dav-Tech
Hardcoating meets or exceeds all requirements of MIL-A-8625,
Type III, and other military and commercial specifications.
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