The test standard summaries are for general guidance only. Though believed to be accurate at the time of writing, this may change over time. So this information should not be used as a substitute for referring to a complete test standard, at an appropriate revision level.
Note: the terms salt spray, salt mist & salt fog are all in wide spread use within corrosion test standards. In this context they can be considered to be equivalent and interchangeable terms.
VDA 621-415 (Constant Climate)
Testing of Corrosion Protection of Vehicle Paint by Alternating Cycles Test
This test procedure has been developed to judge the corrosion protection of vehicle paint using an accelerated laboratory test. It is claimed that testing according to this procedure can generate results that correlate well with those seen by driven vehicles. 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 that comprises of the following 3 part repeating cycle. 24.0 hours exposure to salt spray according to DIN 50 021-SS. This is followed by 96.0 hours exposure to a condensing water climate according to DIN 50 017-KFW. This is followed by 48.0 hours exposure to an ambient climate of +18 to +28C according to DIN 50 014. The number of cycle repeats and therefore the test duration is variable.
Please see elsewhere in this document for details of DIN 50 021-SS, DIN 50 017-KFW & DIN 50 014.
This test is also referred to as a Cyclic Corrosion Test, often abbreviated to CCT.
For further information on VDA standards visit; www. vda.de