Evaluating the Flash Rust Protection of Water-Based Cleaners and Their Role in Surface Preparation

In metalworking processes, contaminants can interfere with future processing steps and may accelerate corrosion on metal parts. As such, a cleaning step is often implemented prior to coating or packaging finished parts. Industrial cleaners are typically water-based with blends of surfactants, co-solvents, chelating agents, and/or flash rust inhibitors. While accelerated corrosion tests such as humidity and salt fog exist, they are typically too aggressive for the evaluation of flash rust inhibitors in cleaners which are not meant to provide long-term corrosion protection. There is a need in the industry for a quick and reliable way to select a cleaner that meets the needs of the application and is compatible with the overall process. A screening method to compare the flash rust protection ability of various water-based cleaners was investigated. Modified vapor inhibiting ability (VIA) testing and linear polarization resistance (LPR) tests were performed on carbon steel plugs treated with several cleaners. Industry standards currently recommend that any detergent or cleaner be removed from metal surfaces prior to applying coatings. When evaluating cleaning processes where coatings will be subsequently applied, adhesion testing should be paired with the screening test. The effects of various cleaners on adhesion of a waterborne acrylic coating were investigated.
Product Number: 51324-20745-SG
Author: Lisa Marston; Luke Stone
Publication Date: 2024