Surface treatment is a process of changing the surface of metal materials:

Surface treatment is a process of changing the surface of metal materials:

Dalian metal surface treatment is an ancient technology that has been mastered by humans since the existence of humans on Earth. The life of primitive humans was difficult, living in groups. In order to survive, they made stone tools and used grinding technology to make the stone tools have sharp edges, producing a "sharp cutting" effect. In the Neolithic era, the stone tools used by primitive people were polished throughout, with a delicate and smooth surface.

Dalian Metal Heat Treatment is a process that heats metal workpieces in a certain medium to a suitable temperature, maintains this temperature for a certain period of time, and then cools them in different media at different speeds. By changing the microstructure of the metal material surface or interior, its properties are controlled. The content of surface protection: electroplating, coating, chemical treatment layer; Electroplating includes (galvanizing, copper, chromium, lead, silver, nickel, tin, cadmium, etc.); Painting includes (paint coating, electrostatic powder spraying, spray molding process); Chemical treatment includes (blackening treatment, phosphating treatment).

The main method is to use acidic or alkaline solutions to chemically react with the oxides and oil stains on the surface of the workpiece, dissolve them in acidic or alkaline solutions, in order to remove rust, oxide skin, and oil stains on the surface of the workpiece. Then, use a nylon brush roller or 304 # stainless steel wire (a steel wire brush roller made of acid and alkali resistant solution) to clean and achieve the goal. In order to remove various foreign objects attached to the surface of the object (such as oil stains, rust, dust, old paint films, etc.), provide a good substrate suitable for painting requirements, and ensure that the coating has good anti-corrosion performance, decorative performance, and certain special functions, the surface of the object must be pre treated before painting.

People refer to the work done by such treatment as pre coating (surface) treatment or (surface) pre-treatment. The passivation and rust prevention treatment of metal surfaces is becoming increasingly important. Rust prevention treatment can greatly increase the corrosion resistance of products and prolong their service life. Even stainless steel products now require stainless steel environmental passivation treatment, otherwise it is difficult to achieve the required anti-corrosion effect. Therefore, during pretreatment, do not use strong alkali and strong acid for degreasing and etching. Because strong alkali can dissolve the rich aluminum first, while strong acid can dissolve the rich zinc phase first, forming pinholes and micro pores on the surface of die castings, and leaving behind strong alkali and strong acid solution, it is easy to cause peeling and produce bubbles after coating.

The multi-layer chromium plating layer is a cathodic protection coating of zinc alloy, so the coating must have a certain thickness to ensure that there are no pores in the coating. Otherwise, due to the negative electrode potential of zinc alloy, it is easy to produce white powdery corrosion products of alkaline zinc carbonate in humid air. Therefore, it is necessary to choose an appropriate coating thickness based on the product's usage conditions.