Correlation between accelerated laboratory tests and field tests for filiform corrosion of painted aluminum alloy sheets for automobile

摘要

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.