Vice president, Suga Test Instruments Co., Ltd, Tokyo,
Pages: 16 Published: Jan 1994
At present there are no established test methods for corrosion due to acid rain. The authors carried out experiments to find an adequate simulated acid rain corrosion test method.
Various types of cyclic corrosion tests (CCT) for automotive metallic materials have been widely utilized in Japanese automotive industries and a test method (JASO M 609) was standardized in 1991. This method is based on cyclic procedure in which one cycle comprises 2 hours of salt spray using neutral 5% sodium chloride solution, 4 hours of dry-off and 2 hours of damp heat.
The simulated acid rain test we developed is based on CCT method, except for the test solution which is prepared by adding nitric acid and sulfuric acid to neutral 5% sodium chloride solution. The experiments included tests on four standard bare metals (copper, zinc, aluminium and steel), and metallic and paint coatings on steel.
45 cycles in the Acid rain CCT device correspond to one year of outdoor exposure in the Tokyo area and on Okinawa in reproducing the deterioration of paint coatings as well as metallic coatings.
corrosion, cyclic corrosion test, acid rain
Paper ID: STP18183S