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.
Toyota 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 used in vehicle bodies where there is a significant influence of chloride ions, mainly as sodium chloride from 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 test comprises 3 alternative 24 hour single cycles, methods A, B and C.
Method A comprises 17 hours saltwater spraying, 3 hours forced drying, 2 hours saltwater dipping and finally 2 hours natural drying.
Method B comprises 1 hour saltwater spraying, 16 hours wetting, 4.5 hours forced drying, 1 hour saltwater dipping and finally 1,5 hours natural drying.
Method C comprises 4 hours saltwater spraying, 5 hours forced drying, 12 hours wetting, 2 hours forced drying and finally 1 hour natural drying.
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.