A Volvo accelerated laboratory corrosion test to evaluate corrosion resistance

Introduction

The Volvo VCS 1027, 1449 test (also known as ACT-2) is a test method developed to evaluate the corrosion resistance of metals, especially in environments with a high concentration of sodium chloride from a marine influence or from winter de-icing solutions.

The test has a number of potential uses in the verification of design changes;

To improve the performance of corrosion resistant products and materials.
Assisting in the development of new and improved pre-treatments and finishing processes.
Assisting in the quality control of manufactured products.

The Volvo VCS 1027, 1449 standard was developed in conjunction with Ford and is equivalent to CETP 00.00-L-467.

Test Conditions

The test method is composed of approximately 0.5% NaCL salt mist applications combined with a drying and controlled temperature and humidity phases, the length of the test process is variable.

The recommended specification for the equipment required to undertake this test includes the use of oscillating spray nozzles located high up in the test chamber. These spray salt water solution down on to test samples located beneath, in a precise spray pattern, to ensure a uniform distribution.

Method

Specimens to be tested are exposed to a variety of environmental conditions, the first 5 days comprising of the following three part repeating cycle;

• A 6 hour continuous wet phase at 25°C at 95% RH with intermittent exposure to salt spray, the salt spray being applied at least at the beginning, in the middle and at the end of this phase.  This stage should be undertaken without drying or with humidity control set to ensure there is no drying of the samples.
• 2.5 hours of drying, a two stage process that enables an end of phase transition to 50°C & 70% RH.
• 15.5 hours of controlled temperature and humidity at 50°C and 70%RH.

Following 5 days of repeating cycles of the above there should be 48 hours exposure to a constant climate of 50°C and 70%RH.

Typical Application

This corrosion test is utilised widely by Volvo and by their suppliers as a quality audit of coated parts.

If you would like further information please call our experienced team on 01827 318040 or email sales@ascott-analytical.com