Electric galvanized：
Steel is easy to rust in the air, water or soil, or even completely damaged. The annual steel loss due to corrosion accounts for about 1/10 of the entire steel output. In addition, in order to give the surface of steel products and parts a special function, while giving them a decorative appearance, they are generally treated by electro-galvanizing.
① Principle:
Since zinc is not easy to vary in dry air, in humid air, the surface can generate a very dense base-type carbonate film, which can effectively protect the inside no longer corrosion.
② Performance characteristics:
1. The zinc coating is thick, with fine crystals, uniformity and no porosity, and good corrosion resistance;
2. The zinc layer obtained by electroplating is relatively pure, and corrodes slowly in the mist of acid, alkali, etc., and can effectively protect the steel substrate;
3. The zinc coating is passivated by chromic acid to form white, colorful, military green, etc., which is beautiful and decorative;
4. Because the zinc coating has good ductility, it can be formed by cold punching, rolling, bending, etc. without damaging the coating.
③ Application scope:
With the development of scientific and technological production, the fields involved in the electroplating industry have become more and more extensive. At present, the application of electro-galvanization has spread to various production and research departments.
Hot galvanized:
Ⅰ. Overview:
In the coating method of various protected steel matrix, hot dip is very excellent. It is in a state where the zinc is liquid, after a relatively complex physics, chemical, not only a thicker pure zinc layer not only plated on the steel, but also a zinc-ferrous layer. This plating method not only has a corrosion resistance characteristic of electric galvanization, but also due to a zinc iron alloy layer. It also has strong resistance to electroplated zinc. Therefore, this plating method is particularly suitable for a strong corrosive environment such as a variety of strong acid, alkaline mist.
Ⅱ. Principle:
The hot-dip galvanized layer is zinc in high temperature liquid, and is formed by three steps:
1. The iron-based surface is dissolved by zinc solution to form a zinc-ferrous phase;
2. Zinc ions in the alloy layer are further diffused to the substrate to form a zinc iron intercollation layer;
3. the surface of the alloy layer is enclosed in the zinc layer.
Ⅲ. Performance characteristics:
(1) Has a thicker dense pure zinc layer covers on the surface of the steel, which avoids the contact of the steel matrix from any corrosion solution to protect the steel matrix from corrosion. In the general atmosphere, the surface of the zinc layer forms a thin layer of thin and intimate zinc oxide layer, which is difficult to solute in water, so the steel matrix plays a certain protective effect.
(2) With iron-zinc alloy layer, combined with dense, in the marine salt humex atmosphere and industrial atmosphere demonstrated unique corrosion resistance;
(3) Since the combination is firm, zinc-iron is solubilized, it has strong wear resistance;
(4) Since the zinc has a good ductility, the alloy layer is securely attached to the steel group, so the hot plating parts can be cold-plated, rolled, brushed, curved, and the like without damaging the coating;
(5) After hot galvanization of steel finisse, it is equivalent to annealing treatment, which can effectively improve the mechanical properties of the steel matrix, eliminate the stress of the steel molding welding, which is advantageous for turning the steel structural member.
(6) The surface of the pieces after hot galvanization is bright and beautiful.
(7) The pure zinc layer is the most plastic-plastic-plated galvanized layer in hot galvanized, which is substantially close to pure zinc, ductility, so it is flexible.
Ⅳ. The scope of application:
The application of hot-dip ghanelyly the development of industrial and agricultural development. Therefore, hot-dip ghared products are industrial (such as chemical equipment, oil processing, marine exploration, metal structure, electricity delivery, shipbuilding, etc.), agriculture (such as: sprinkling), architecture (such as water and gas delivery, wire set Tube, scaffolding, house, etc.), bridge, transportation, etc. have been used in a number of recent years.
Since hot-dip galvanized products have a beautiful appearance, good corrosion resistance performance, its application range is increasingly wide.
Post time: Jan-29-2023