Screw plating is a common surface treatment used to improve the properties of screws, such as increasing corrosion resistance, adding aesthetics, increasing hardness or improving electrical properties. Electroplating is the process of depositing a layer of metal on the surface of a screw by means of electrolysis.
Author: Anna
Screw plating is a common surface treatment used to improve the properties of screws, such as increasing corrosion resistance, adding aesthetics, increasing hardness or improving electrical properties. Electroplating is the process of depositing a layer of metal on the surface of a screw by means of electrolysis.
In a plating bath, the screw acts as the cathode and the target metal acts as the anode, both of which are immersed in an electrolyte solution containing ions of the target metal. When an electric current is passed through the electrolyte, the metal ions are reduced and form a plating layer on the surface of the screw.
Common types of screw plating include:
Galvanizing: This is one of the most common types of screw plating and its main purpose is to prevent rust and corrosion. Galvanizing can be either Electroplating or Hot-dip galvanizing, the latter usually providing a thicker coating.
Nickel Plating: provides better corrosion and abrasion resistance and can also be used as a base layer for other plating such as chrome plating to enhance bonding.
Chromium Plating: is a very hard layer that improves the wear resistance and gloss of the screws and also provides some corrosion resistance.
Oxidation: This is not plating, but a chemical reaction that forms an oxide film on the metal surface, such as the black oxide treatment commonly used in military or aerospace applications.
Chemical Plating: Unlike electroplating, chemical plating does not require an electric current, it deposits a metal layer on the surface of the screw through a chemical reaction, such as nickel chemical plating (Nickel Chemical Plating), which is usually very uniform, even in complex shapes of screws can also achieve good coverage.
Each plating method has its own specific application scenario, and the choice of which plating to use depends on the specific conditions of use of the screw and the desired performance characteristics. For example, screws used outdoors may require a heavier zinc plating to resist harsh weather conditions, while screws in precision instruments may require nickel or chrome plating to improve accuracy and aesthetics.