Corrosion test method for Automotive Materials
This standard specifies a test method to determine the corrosion resistance of steel sheets for automotive use. It 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. 2.0 hours exposure to salt spray at +35C according JIS Z 2371. This is followed by 4.0 hours of air drying in a climate of 20 to 30%RH at +60C. This is followed by 2.0 hours exposure to a condensing water climate (wetting) of 95 to 100%RH at +50C. The number of cycle repeats and therefore the test duration is variable.
The maximum transition times between each part of the test cycle are also specified as follows:
From salt spraying to air drying within 30 minutes.
From air drying to wetting within 15 minutes.
From wetting to salt spraying within 30 minutes.
Please see elsewhere in this document for details of JIS Z 2371.
Chamber volumes of less than 400 Litres are not permitted by this test standard.
This test is also referred to as a Cyclic Corrosion Test, often abbreviated to CCT.
This is an accelerated laboratory corrosion test method that can be used to determine the corrosion resistance of automotive assemblies and components. It 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 a relatively short period of salt spray, followed by exposure to hot/humid and hot/dry atmospheres. The entire test cycle comprises of a main cycle and a sub-cycle. 1 entire test cycle takes 24 hours to execute. The number of entire cycle repeats and therefore the test duration is variable.
The main test cycle begins with 10 minutes exposure to a continuous indirect spray of salt water solution, in a chamber temperature of +35C . This is followed by 155 minutes of air drying at +60C. This is followed by 75 minutes exposure to a high humidity climate of 95%RH at +60C.
This is then followed by a repetitive sub-cycle comprising of 160 minutes of exposure to an air drying at +60C, followed by 80 minutes exposure to a humid climate of 95%RH at +60C. This sub-cycle is repeated 5 times in total, before the main test cycle starts again.
This is an accelerated laboratory corrosion test method that can be used to determine the corrosion resistance of automotive assemblies and components. It 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. 2.0 hours exposure to a continuous indirect spray of neutral (pH 6.5 to 7.2) salt water solution, which falls-out on to the specimens at a rate of 1.0 to 2.0ml/80cm²/hour, in a chamber temperature of +35C . This is followed by 4.0 hours of air drying in a climate of 20 to 30%RH at +60C. This is followed by 2.0 hours exposure to a condensing water climate (wetting) of 95 to 100%RH at +50C. The number of cycle repeats and therefore the test duration is variable.
The maximum transition times between each part of the test cycle are also specified as follows:
From salt spraying to air drying within 30 minutes.
From air drying to wetting within 15 minutes.
From wetting to salt spraying within 30 minutes.