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Accelerated Weathering
Tests
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Weatherometer,
ASTM G153
This device uses a combination of carbon arc
UV radiation and water spray to simulate destructive weather conditions
in an accelerated manner. Although precise equivalents are impossible
to determine, a practical calculation is: 300 hours in the Weatherometer
equals one year real time.
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Thermal
Shock Chamber, 
ASTM D2337
This is simply a temperature control device
in which temperature can be raised or lowered over a controlled
period of time. This is done to simulate the extreme conditions
found in nature and as a means of inducing coating failure.
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Seawater
Spray (Fog) Chamber, 
ASTM B117
Seawater is atomized with a special device
and allowed to condense in an even manner on the surface of the
test panels. The length of exposure is specified by the United States
Navy’s standards, which is 300 hours below deck and 500 hours
above deck.
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Seawater
Immersion Resistance, 
ASTM D870
A plastic tank is filled with seawater and
the panels are suspended from a line with plastic shims between
the panel suspension holes. The panels are soaked in seawater for
336 hours and then removed for final inspection.
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Mechanical Tests
Taber
Abrasion Test, ASTM D4060 
This mechanical test is performed using a Taber Abraser Machine.
The Taber Abraser requires a specific size of panel and cycles that
panel on a horizontal plain against an abrasive wheel at a given
angle and pressure. The cycles are continued until the abrasive
wheel wears through to the metal underneath the coating. The greater
the number of cycles required to reach the metal, the more abrasion
resistant the coating is.
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Mandrel
Bend Test, ASTM D522 
In this test, a panel with one side coated is bent 180 degrees around
a 3/8 inch steel mandrel. The condition of the coating at the “bend
site” is visually examined and evaluated according to the
criteria in ASTM D522.
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Impact
Resistance Test, ASTM D2794 
This procedure defeats all but the best coatings.
A ½ inch steel ball is dropped from a predetermined height
onto a steel panel with the test coating applied to the underneath
side. After impact, the bulge on the coated side of the panel is
examined for coating damage and separation from the steel underneath
the coating.
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Crosshatch
Adhesion Test, ASTM D3359 
This rigorous mechanical test involves cutting a grid of 100 squares
into a coated panel. A pressure sensitive tape is applied over the
grid, and then rapidly peeled away. The number of squares remaining
on the panel gives a relative percentage value of adhesion.
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Please visit the National
Testing Standards Website:
http://www.nationaltestingstandards.com/
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