For a current density of 20 amperes per square meter--
- Freshwater, 10 grams per ampere-year.
- Saltwater, 15 grams per ampere-year.
A Gardner heavey-duty impact tester (Pacific Scientific, West Silver Spring, MD) shall be used. The anode
will be screwed into a modified holder and a round-nose punch 0.625 inches in diameter will be placed on
the specimen. A 2-pound weight shall be raised to the desired height in a graduated tube and released.
Damage to coatings, such as chipping or cracking, should be observed visually or with low-power (10X)
magnification. The sample should withstand a force of 32 inch-pounds when the weight is dropped; the punch
should be located within an area c inch from the center of the anode without observable damage.