Correlation between accelerated Laboratory Tests and Filed Tests for Filiform Corrosion of Painted Aluminium Alloy Sheets for Automobile
Hiroo Shige, Takenori Nakayama, Kouki Ikeda, L.F. Vega and E.L.Colvin
Abstract:Correlation between laboratory tests and field tests for filiform corrosion of painted aluminum alloy sheets for automobile was investigated by conducting 6 kinds of laboratory tests with different pH, dry-wet condition, etc., and 2 sites of outdoor exposure tests, and vehicle test. It was found that susceptibility to filiform corrosion in the laboratory tests increased with the decrease of pH and/or the increase of repetition rate of wet/dry cycle, and that correlation between outdoor exposure tests and vehicle test was low. In conclusion, the laboratory tests with relatively low wet ratio(70%) correlated well with the outdoor exposure tests, and the tests with relatively high wet ratio(95%) correlated with the vehicle test. Key Words:Filifrom corrosion, Aluminum alloy, Automobile, Outdoor exposure test, Accelerated test, Vehicle test