Release time：2020-01-16 18:44 Browse：
When discussing the difference between different surface treatments of the three-combination extension screws with the cup head hexagonal socket, and which surface treatment is more effective in rust prevention, we first need to understand the basic purpose and importance of screw surface treatment. As an indispensable component in mechanical connection, the performance of screws directly affects the stability and durability of the entire system. The surface treatment can not only improve the appearance of the screw texture, but more importantly, it can enhance its corrosion resistance, wear resistance, fatigue resistance and improve the binding force with the substrate, thus extending the service life.
First, common screw surface treatment process
1. Galvanized treatment
Galvanizing is one of the most common screw surface treatments. By plating a layer of zinc on the surface of the screw, the activity of zinc is prioritized to react with oxygen in the environment to form a dense zinc oxide protective film, which effectively prevents further oxidation of the internal metal and achieves the purpose of rust prevention. Galvanizing treatment is divided into hot dip galvanizing and electric galvanizing, hot dip galvanizing coating is thicker, strong corrosion resistance, suitable for outdoor environment; Electrogalvanizing has uniform coating and smooth surface, which is suitable for indoor or light corrosion environment.
2. Nickel plating
Nickel-plated screws have excellent corrosion resistance, wear resistance and decoration. The nickel layer can effectively isolate air and moisture to prevent screws from rusting. At the same time, the nickel layer also has good ductility, which can alleviate the stress concentration caused by the screw in the fastening process to a certain extent. Nickel-plated screws are mostly used for occasions requiring beautiful appearance and high corrosion resistance.
3. Dacromet handles
Dacromet is a new anti-corrosion surface treatment technology, mainly composed of zinc powder, aluminum powder, chromate and organic solvents. It is baked at high temperatures to form a strong anti-corrosion coating on the screw surface. Dacromet treated screws not only have strong corrosion resistance, but also maintain high adhesion in harsh environments and are not easy to flake. In addition, Dacromet coating also has the advantages of no hydrogen embrittlement, high heat resistance, etc., especially suitable for anti-corrosion treatment of high-strength bolts.
4. Blackening treatment (blue treatment)
Blackening treatment, also known as bluing treatment, is through chemical oxidation to form a dense oxide film on the screw surface. This treatment method has the advantages of low cost and simple process, but the anti-rust effect is relatively weak, and it is mainly used for occasions where the anti-rust requirements are not high. The surface of the screw after blackening is dark black, which has certain aesthetics and wear resistance.
5. Sand blasting
Sandblasting is not a direct means of rust prevention, but it can significantly improve the roughness of the screw surface, improve the adhesion of the coating, and lay the foundation for subsequent anti-corrosion treatment. After sandblasting, the screw surface is more uniform, which is conducive to the uniform adhesion of the anti-corrosion coating, thereby indirectly improving the anti-rust effect.
Second, which surface treatment is more rust resistant?
Comprehensive comparison of the above surface treatment methods, from the point of view of anti-rust effect, dacrosol treatment is usually considered to be one of the best anti-rust methods because of its unique coating structure and excellent anti-corrosion properties. Especially in harsh environments such as high humidity and high salt spray, Dacromet treated screws can show excellent corrosion resistance and effectively extend the service life.
However, it is worth noting that the choice of surface treatment needs to be considered according to the specific application scenario, cost budget and environmental protection requirements. For example, where a beautiful appearance is required and the cost is relatively low, nickel plating may be more appropriate; In the environment with strict requirements for environmental protection, it is necessary to consider the use of low pollution or pollution-free surface treatment technology.
Iii. Conclusion
In summary, the different surface treatment processes of the cup head hexagonal three-combination extension screws have their own advantages, and their anti-rust effects are also different. In the selection, the use of the product environment, performance requirements and cost budget should be fully considered, so as to choose the most suitable surface treatment. At the same time, with the progress of science and technology and the improvement of environmental awareness, more efficient and environmentally friendly screw surface treatment technologies will emerge in the future, bringing more innovation and convenience to the field of mechanical connection.
