SWAAT Test – ASTM G85:A3

ASTM G85:A3 Acidified Synthetic Sea Water Testing (SWAAT Test)

Touchstone has several salt spray cabinets and can conduct both standard and customized testing.

ASTM G85 Annex 3 (A3) SWAAT test is a corrosion test that uses synthetic sea salt instead of traditional sodium chloride. The solution is then acidified using glacial acetic acid. This test is to be operated under wet bottom conditions.

Salt Solution: A synthetic sea salt solution made with the addition of glacial acetic acid.

pH Range: 2.8 – 3.0

Test Temperatures: The temperature of the saturator tower (bubble tower) is to be kept at 47 +/- 1°C (117 +/- 2°F) if the cabinet temperature is 35°C (95°F); and 57 +/- 1°C (135 +/- 2°F) if the cabinet temperature is 49°C (120°F). These temperatures are however variable and may be changed to suit the material being testing.

Test Cycle: ASTM G85 Annex 3 (A3) SWAAT utilizes the following cycle: 30 minute spray followed by a 90 minute soak at above 98% relative humidity.

Additional Information: This test can be used to determine time to perforation primarily on aluminum alloy brazing sheet used to manufacture heat exchangers, or even complete heat exchangers under pressure, or other parts. It can also applicable to determine how varying heat treatment parameters affect corrosion behavior. Testing of organic coatings on metal substrates can also be conducted, where a lower temperature is typically used to prevent paint blistering.

This test was originally published as ASTM G43, prior to the current ASTM G 85 Annex 3 (A3). SWAAT stands for Sea Water Acetic Acid Test.

Sample preparation and placement: Touchstone has tested both coupons and entire components for automotive, aerospace, and other industries. If you are interested in coupon testing, we can prepare and coat the edges, to eliminate edge corrosion.

Samples are typically placed at a 15-30 degree angle from vertical, however components for aerospace or automotive are generally oriented in the “as used” position. Samples are located so condensate from one sample does not drip onto another sample.

Test time ranges from 24 to thousands of hours, usually in 24 hour increments. We can recommend a test length, and also an inspection frequency. We have several cabinets that can run different salt spray tests.

Additional related tests and analysis: In addition to ASTM G 85 Annex 3 (A3) SWAAT, Touchstone performs other corrosion testing such as CASS testing. We can also conduct tests to third party specifications in the aerospace, military, or automotive areas such as GM SWAAT corrosion testing specification GME 60 213.

Consulting on corrosion problems is also available. Our light microscopy, metallography, and mechanical testing laboratories can provide a full suite of tests to support your material characterization program.