Methods & requirements

Volvo standard VCS 1027,1449 test

Corrosion testing determines the resistance of materials to corrosion under specific environmental conditions, like temperature and humidity. Other accelerating factors can be presence of chemicals and the pH-level of the salt fog and pluviometry.

There are mainly two different types of corrosion test standards, field performance and accelerated corrosion tests. Proton Technology is focused on different types of standardized corrosion tests.

What is important when choosing a test method is to make sure the controlled environment matches the natural outside environment in terms of behaviour of the protective coating when it degrades. Since the methods used in a laboratory environment are accelerated, studies must underpin the extrapolation of test duration.

Control Art Chambers used for Volvo standard VCS 1027, 1449

Accelerated corrosion testing by Volvo VCS 1027,1449, ACT II

The test standard Volvo VCS 1027,1449 describes a test method called ACT II which is an abbreviation of accelerated corrosion test, ACT, version II, and is a cyclic corrosion test method used for testing the corrosion resistance on vehicle parts. The standard Volvo standard VCS 1027,1449 defines a laboratory accelerated atmospheric corrosion test method to be used in assessing corrosion resistance of metals influenced by chloride ions from salt spray solution. The test is performed by simulating atmospheric corrosion conditions in a controlled way and it serves as a general-purpose atmospheric corrosion test and applies to a variety of materials, coatings, and interactions of materials, both in the form of test pieces or designed components. The test can be used as a design verification method to:

Develop and qualify new corrosion resistant products
Develop new pretreatments and finishing processes
Select materials and
Perform quality control of the finished product.

Test procedure and assessment

Samples to be tested for corrosion resistance according to Volvo VCS 1027,1449, are tested in controlled climate chambers during a defined exposure time. The exposure time in the test chamber is described by requirement standards and requirement level and depends amongst other on the surface treatment of the test samples.

The accelerated corrosion test is finished when the specified exposure time for the test samples is reached. Upon finishing the corrosion testing the samples are evaluated for corrosion resistance. Several assessments are applicable to evaluate corrosion resistance for example by evaluation general corrosion, propagation from scribe and spontaneous propagation at edges.

Test cycle

During a cyclic corrosion resistance test according to Volvo VCS 1027,1449 the atmospheric corrosion conditions are accelerated using a cyclic corrosion test method in a controlled chamber.

The test cycles consist of controlled humidity and temperature cycling with application of salt solution by rain phase containing sodium chloride. One test cycle corresponds to one week of testing. The one-week test cycle is composed of two twelve-hour sub-cycles. Sub-cycle 1 consists of controlled and intermittent exposure to varied temperature and humidity, combined with salt application by salt spray exposure that consist of 0.5% NaCl solution. Sub-cycle 2 contains of constant temperature and humidity.

The variation in temperature is 25-50 degrees C and the relative humidity (humidity % RH) reaches from 70 to 95. The complete one-week test cycle consists of 5 repetitions of sub-cycle 1 followed by 2 repetitions of sub-cycle 2.

Corrosion resistance requirements

Corrosion resistance requirements for samples tested by Volvo VCS 1027,1449 are specified by requirement standards. The requirements depend on the substrate and coating of the samples and the environment the samples are exposed to during position in the vehicle.

Example of requirement standards where accelerated corrosion testing by test method Volvo 1027,1449 ACT II is required are: