Powder Coating vs. Electrophoretic Coating + Powder Coating

Four steel enclosure samples were used in the comparison. The samples were divided into two groups, with two samples in each group.

All four samples were placed in the same chamber and exposed simultaneously to reduce variations caused by equipment conditions, test duration and salt spray concentration.

Before entering the salt spray chamber, all four samples were visually inspected and photographed. The initial images provide a reference for evaluating later changes in the coating surface, edges, punched openings, screw holes and other exposed areas.

The first detailed inspection was performed after 163 hours of continuous salt spray exposure. At this stage, the samples were photographed to document any visible changes in coating condition and the early development of corrosion.

The final documented inspection was completed after 243 hours of salt spray exposure. The same inspection points used at 163 hours were reviewed again to identify whether corrosion had expanded, remained localized or appeared in additional areas.

The timeline below is designed to compare each coating system at three stages: before testing, after 163 hours and after 243 hours.

This comparison is intended to show how two coating systems behave under the same accelerated salt spray exposure conditions. Once all images are reviewed, the final analysis will focus on where corrosion first appeared, how quickly it developed and whether the electrophoretic coating base layer provided additional protection in vulnerable areas.

The most important comparison is not simply whether rust was present. The location, timing and rate of corrosion development are also relevant when assessing the performance of a coating system.

Daheng Electric uses internal testing to better understand how materials, surface treatment and manufacturing processes influence the durability of AC disconnect enclosures.

The purpose of this test is not only to present a final result, but also to document the testing process, compare coating systems and support future process improvement.