October 17, 2023
Corrosion is an electrochemical oxidizing process that affects the appearance and performance of metals and other materials. For electronic equipment, exposure to even mildly corrosive environments can create a range of problems that go beyond appearance. These include connector interface and contacts discontinuities, which then manifest as intermittent electrical faults or permanent failures. Salty atmospheres accelerate conductive bridging across circuit board traces and cause electrical shorts. Corrosion can also weaken structural elements and fasteners and degrade the adhesion of paints, films, and coatings.
To evaluate electrical device and other items for resilience to corrosive and oxidizing environments, standardized tests are available to perform the assessment. The most common tests include exposing products to a 100% saturated humid environment consisting of a steady state 5% NaCl salt fog. Typical standards for these environments include ASTM B117, MIL-STD-810 Method 509, and IEC 60068-2-11. These tests run continuously for a specified period of hours, or in the case of MIL-810 the exposure is applied in one or more cycles of in-chamber fogging then out for a drying period.
An even more aggressive test that accelerates corrosion is IEC 60068-2-52. This standard cycles through a sequence of conditions starting with a salt fog wetted period, followed by damp humidity then dry conditions, and then repeated for multiple cycles. The cyclic nature of fog exposure followed by humid and dry periods is effective at reproducing the effects of natural environments and can accelerate the corrosion mechanism. Because of its robust nature, IEC 60068-2-52 is adopted as the corrosion and salt fog validation standard for many passenger car and commercial vehicle OEMs.
Elite’s Cyclic Salt Mist Chamber
Elite’s new Cyclic Corrosion Test Chamber is uniquely designed to run the IEC 60068-2-52 test and complete it efficiently and accurately. Since this test includes cycles that can last up to 60 days or more, an automated chamber such as Elite’s is critical for time and cost savings.
The chamber internal dimensions are 76″ long x 45″ deep to support testing of larger assemblies or testing of multiple samples. It is also configurable for a wide range of common corrosion tests like ASTM B117, ASTM G85, and SAE J2334. In addition, specialty corrosion tests are supported including for Copper-Accelerated Acetic Acid Salt Spray (CASS) and Acetic Acid Salt Spray (AASS).
For more information on this new service and our chamber capabilities, contact Elite today to discuss your salt fog and cyclic corrosion testing requirements.