The surface treatment of stainless steel grating can not only enhance its appearance texture, but also enhance its corrosion resistance and prolong its service life. According to the different requirements of application scenarios, common surface treatment methods can be divided into the following categories:
Mechanical polishing is the most widely used processing method, which grinds the surface of the grid using tools such as grinding wheels and cloth wheels. During the rough polishing stage, coarse sandpaper is used to remove surface oxide scale and scratches. For medium polishing, a medium coarse grinding wheel is used to refine the grain, while for fine polishing, a wool wheel combined with polishing paste is used to achieve a mirror effect. This method can significantly reduce the surface roughness of the grille, making it suitable for scenarios with high aesthetic requirements such as building decoration. However, special treatment is required at the corners to avoid burrs.
Chemical polishing does not require complex equipment. The grid is immersed in a polishing solution composed of nitric acid, phosphoric acid, sulfuric acid, etc., and the surface micro protrusions are dissolved through chemical reactions. During processing, it is necessary to control the appropriate temperature and adjust the time flexibly according to the surface condition. This process can uniformly process complex structures and is suitable for large-scale production, but it may generate harmful waste liquid and requires environmental protection treatment equipment. After treatment, the surface appears uniformly matte, and the corrosion resistance is significantly improved.
Electrolytic polishing is a combined process of chemistry and electrochemistry, in which a grid is placed as an anode in an electrolytic cell. Under the action of direct current, surface metal ions migrate and dissolve in a directional manner. Electrolytes often use a mixed solution of phosphoric acid and sulfuric acid, and appropriate voltage and current density should be set. This method can achieve a more uniform mirror effect than mechanical polishing, and form a passivation film on the surface. It has excellent salt spray resistance and is particularly suitable for corrosive environments such as chemical and marine engineering.
Sandblasting treatment uses high-pressure airflow to spray abrasive materials such as diamond sand and glass beads onto the surface of the grille, forming a uniform rough texture. According to the different abrasive particle sizes, high-quality rust removal can be achieved, forming a suitable surface roughness. The surface after sandblasting can enhance the adhesion of the coating and is often used as a pre-treatment process before spraying. It can also be directly used in places that require anti slip effects, such as sewage treatment plant operation platforms.
Spray coating treatment includes two types: powder coating and fluorocarbon coating. Powder coating is a process in which epoxy resin powder is electrostatically adsorbed onto the surface of a grid, and then cured at high temperatures to form a coating of a certain thickness. The color can be customized and the weather resistance is strong; Fluorocarbon spraying uses polytetrafluoroethylene coating, which forms a dense protective film after high-temperature baking. It has excellent UV aging resistance and is suitable for outdoor building decoration, with a long service life.
After surface treatment, quality inspection is required: surface accuracy is measured using a roughness meter, corrosion resistance is verified through salt spray testing, and adhesion testing is conducted to ensure coating bonding strength. The combination of different processing techniques (such as sandblasting+spraying) can balance functionality and aesthetics, meeting diverse application needs. In practical operation, the most suitable treatment plan should be selected based on the material grade of the grille (such as 304, 316) and the usage environment.
