Accelerated corrosion test
This standard defines an accelerated corrosion test method to be used in assessing the corrosion resistance of metals in environments where there is a significant influence of chloride ions, mainly as sodium chloride from a marine source or by winter road de-icing salt. It specifies a test procedure to be used in conducting the accelerated corrosion test to simulate atmospheric corrosion conditions in a controlled way.
The one-week main test cycle is composed of two twelve-hour sub-cycles, one with controlled humidity cycling; sub-cycle 1, the other including salt solution application, sub-cycle 2.
Sub cycle 1 requires constant conditions at 35°C & 95% RH for 4 h, followed by an increase of temperature to 45°C whilst reducing the humidity to 50% over a 2 hour period. This is followed by constant conditions of 45°C & 50% RH for 4 h, together with a 2 hour period of 35°C & 95% RH. Step 1:4) Temperature decrease from 45°C to 35°C
Sub cycle 2 requires spraying with salt solution for 15 mins then keeping the samples at 35°C for 1 h 45 min whilst maintaining a set point of 95% – 99% RH in such a way that the test objects remain wet. These steps are repeated in sequence to give a total period of 6 hours. Drying at 45°C & 50% RH for a 2hour period followed by a further 2 hour period of 35°C whilst maintaining 95% RH.