Scania Laboratory Accelerated Cyclic Corrosion Test
This test procedure serves as a general purpose atmospheric corrosion test and can be applied to a wide variety of materials, coatings and interactions of materials. It has been developed to allow the evaluation of 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. This test is cyclic in nature, i.e. test specimens are exposed to changing climates over time.
Test specimens are placed in an enclosed chamber and exposed to a changing climate. The first 5 days comprise of the following 3 part repeating cycle. 6.0 hours exposure to a ‘wet’ climate of no less than 95% RH, at +25°C, with intermittent exposure to salt solution.
This is followed by 2.5 hours climate controlled transition to 50°C & 70% RH. This is followed by 15.5 hours exposure to a constant climate of 50°C & 70% RH.
The final 2 days comprise of 48.0 hours exposure to a constant climate of 50°C & 70% RH. This completes the total 7 day test cycle. The number of cycle repeats and therefore the test duration is variable.
This test is also referred to as a Cyclic Corrosion Test, often abbreviated to CCT, and is based on Volvo 423-0014.
Scania 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 7 day main test cycle is composed of two twelve-hour sub-cycles, one with controlled humidity cycling, the other including salt solution application.
Sub cycle 1 requires four hours of constant conditions at 35°C & 95% RH, 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 four hours, followed by a 2 hour period of transition to 35°C & 95% RH
Sub cycle 2 requires spraying with salt solution for 15 mins then subjecting the samples to 35°C for one hour forty five minutes whilst maintaining a relative humidity of 95% – 99% RH to ensure the test samples remain wet. These steps are repeated to give a total period of 6 hours. This is followed by drying at 45°C & 50% RH for a two hour period followed by a further 2 hours of 35°C whilst maintaining 95% RH.
This test is also referred to as a Cyclic Corrosion Test, often abbreviated to CCT, and is based on Volvo 423-0014.
