What is rust? Does rust need to be thoroughly removed before applying a corrosion-resistant coating?

Rust is formed when iron reacts with oxygen in a humid environment. Under different conditions, rust can take various forms. It primarily consists of iron(III) oxide hydrate and copper hydroxide. The formation of rust on iron is a chemical reaction. Essentially, it is an oxidation reaction of the metal. Iron rusts over time, not only due to its active chemical properties but also because of external conditions. Moisture is one of the substances that makes iron prone to rusting. However, water alone does not cause rusting. Rust forms only when oxygen from the air dissolves in water and reacts with the iron in the water environment, producing iron oxide. Furthermore, iron oxide hydroxide formed by seawater or atmospheric hydrogen oxidation contains soluble sulphates and sodium chloride, both of which have strong corrosive effects on metals. The potential difference between rust and iron also triggers electrochemical corrosion, which poses significant hazards.

On one hand, it can cause extensive corrosion of the metal surface of equipment in a short period of time. Due to corrosion caused by disuse and the resulting rough surface of the metal, rust is not as simple as it appears on the surface. Therefore, rust must be thoroughly removed before applying anti-corrosion coating; otherwise, the continuous expansion of rust will lead to poor paint film adhesion and anti-corrosion effectiveness. Thus, rust removal treatment of steel is an important component of the coating process and plays a decisive role in the success or failure of anti-corrosion coating.

However, when dealing with large-scale buildings, steel structures, factory equipment, colour-coated steel sheet renovations, reinforcing bars, and other components that are difficult to grind and rust-remove, what effective methods are available to address rust spots?

Our company offers N680 Water-Based Rust Converter, an economical, medium-viscosity water-based rust converter. This product is formulated using functional emulsions and high-molecular-weight rust conversion additives. When applied to rusted surfaces, it reacts with the rust to form a dense, grey-black anti-corrosion protective coating.

Rust Converter N680 Product Performance：

1. Fast drying speed, effectively improving construction efficiency

2. Moderate viscosity, preventing sagging during vertical surface application

3. High cost-effectiveness, high coverage area, and low overall usage cost

4. Eliminates the need for complex pre-treatment processes such as grinding, acid washing, water washing, phosphating, sandblasting, and priming, significantly reducing construction intensity and overall treatment costs.