The process and function of steel blackening

Steel is widely used nowadays. Rusting of steel is a very common phenomenon. Under normal circumstances, phosphating is chosen. In addition, blackening treatment can also be used. Blackening treatment produces a dense black layer on the surface of the steel. Oxide film, achieve the purpose of isolating the air, in order to achieve the effect of rust prevention and beauty.

In industrial production, steel blackening treatment is usually divided into three stages:

The first step is the preparation stage, which can also be called pre-blackening treatment. This step is to clean up the oil, rust, oxide scale, salt slag, etc. on the surface of the steel workpiece. The activation treatment is to prepare for the subsequent blackening treatment. Including boiling, chemical degreasing, pickling, and clamping of workpieces.

The second step is blackening treatment. The steel workpieces that have been pre-treated and activated are cleaned with clean water and placed in the blackening solution for a certain period of time, and the required oxide film will be formed on the surface of the workpiece. If the blackening agent is a high-temperature blackening agent, you must control the blackening liquid, temperature and concentration.

The third step is dipping anti-rust oil treatment, which is an auxiliary processing stage after blackening. This stage is mainly to supplement treatment and dipping anti-rust oil. The purpose of dipping anti-rust oil is to further improve the corrosion resistance of the oxide film layer. , Improve anti-rust properties, increase lubricity and surface gloss, etc.