VCI is an abbreviation of gas phase corrosion inhibitor or volatilization corrosion inhibition. VCI is a molecule that inhibits corrosion. These molecules form a thin protective layer on the metal surface in a closed space, thus playing an anti-rust role.
This invisible protective layer can prevent water vapor and environmental elements from reacting with the metal surface, thus preventing corrosion. When the closed space is opened, the molecules are automatically dissipated without cleaning.
The gas-phase anti-rust film automatically volatilizes VCI at room temperature to inhibit metal corrosion. Under the condition of no direct contact with the metal surface, the surface, inner cavity, pipelines, grooves, and even gaps of metal products can be protected. It is widely used due to its long anti-rust period, simple operation, and low cost.
The vapor phase anti-rust film is to automatically volatilize VCI at room temperature to inhibit metal corrosion. Without direct contact with the metal surface, the surface of metal products, cavities, pipes, grooves, and even gaps can be protected. Because of its long anti-rust period, easy operation, and low cost, it is widely used.
Film formation corrosion inhibition mechanism: the corrosion inhibitor can chemically react with the ions of the metal or the corrosive medium, and as a result, a protective, insoluble or insoluble compound film is formed on the metal surface to prevent the corrosion process from occurring, that is, it acts as a retarder. Eclipse.
Most of these corrosion inhibitors are oxidants, such as chromate, dichromate, nitrate, and nitrite. They interact with the metal to form a protective oxide film or passivation film on the metal surface, thereby separating the metal from the medium mechanically.
Due to the different corrosion inhibition mechanisms of the vapor phase anti-rust film, it can be roughly divided into the ferrous metal anti-rust film, multi-metal anti-rust film, non-ferrous metal anti-rust film, and precious metal anti-rust film.
For the gas phase corrosion inhibition ability of ferrous metal and polymetallic anti-rust film, the general inspection method at home and abroad is the jar method, and the latest inspection method is ion chromatography.
Compared with the wide-mouth flask method, ion chromatography has great advantages: high efficiency, fast speed, and accurate test results.
Quote-[1] Tang Yanqiu, Bai Fang, Liu Hong. VCI material vapor phase anti-rust performance test methods and prospects[C]//2011 National (Wuhan) Anti-rust Lubricant Packaging Academic Exchange Conference and the Fifth Historical (Expanded) Meeting of the Fifth Anti-rust Professional Committee-Green Anti-rust Lubricant Packaging New Technology Forum. 2011
