1、 Why should hardware springs be galvanized for corrosion protection
(1) As hardware, customers first consider the anti rust ability, so they usually choose galvanized and nickel plating to prevent corrosion. Many users like to choose galvanized springs when selecting springs. Of course, this is not only because its galvanized appearance is more beautiful, but also because it can prevent the spring steel wire from oxidizing and rusting after galvanized. Today, Guoyang spring will talk about why the spring is galvanized for corrosion protection.
(2) In order to improve the corrosion resistance of cadmium coating, passivation treatment can be carried out after plating. The thickness of zinc cadmium coating determines its protective ability. Generally, the thickness shall be selected according to the working environment. The recommended thickness of zinc coating is 6-24 μ m； The recommended thickness of cadmium plating layer is 6-12 μ m。
(3) In the sea or high-temperature atmosphere, as well as in the spring in contact with seawater, the spring is used in 70 ℃ hot water, and the cadmium is relatively stable and has strong corrosion resistance. Cadmium coating is brighter and more beautiful than zinc coating, with good soft plasticity and less hydrogen embrittlement. It is suitable for spring protection. However, cadmium is a rare, expensive and toxic element, which causes serious pollution to the environment. Therefore, its use is limited. Therefore, most of the springs used in the aviation, navigation and electronic industries only use cadmium coating as the protective layer.
(4) There are many kinds of metal protective layers. For springs, the metal protective layer is usually obtained by electroplating. The plating protective layer can not only protect the spring from corrosion, but also improve the appearance of the spring. Some electroplating metals can also improve the working performance of the spring, such as improving the surface hardness of the spring, improving the wear resistance of the spring, improving the thermal stability of the spring, and preventing the radiation corrosion of the spring. However, if it is only for the corrosion of the spring, the electro galvanized layer and the cadmium plating layer should be selected generally.
