What are the common surface treatments of self-tapping screws
When many customers come to consult screws, they will ask: Can self-tapping screws be made red? Can it be made golden? Can you make a surface that is smooth and bright enough to illuminate a human figure? Can the surface feel frosted?
Many problems, in fact, these problems can be concentrated on one point, that is the surface treatment of the screw.
Common surface treatments of self-tapping screws include: electroplating, anodizing, passivation, electrophoresis, blackening (blue) and dacromet.
Electroplating is a technique in which the self-tapping screw to be electroplated is used as the cathode to be immersed in a solution containing the metal cation to be electroplated, and the metal is attached to the surface of the
cathode through the action of electricity. The most commonly used electroplating metals are nickel, chromium, tin, copper, silver and gold.
Anodizing is the use of chemical or electrochemical treatment to generate a film layer containing the metal on the metal surface. Most metal materials (such as stainless steel, zinc alloy, aluminum alloy, magnesium alloy, copper alloy,
titanium alloy) can be anodized in a suitable electrolyte.
Blackening, generally adopts alkaline chemical oxidation method, high corrosion resistance. Due to the appearance of the oxide film, it can only be used in general conditions or oily media, or considering the effect of appearance,
blackened screws will be used.
Passivation is to dissolve the iron contaminants hidden on the screw, so that the surface of the screw is opened into a passivated protective film, which can protect the bolt from corrosion and erosion. The general passivation surface
treatment method is applied to electronic products.
Electrophoresis is the use of electrophoresis technology to evenly cover the surface of bolt fasteners with paint, latex, rubber and other particles. After the surface treatment of electrophoresis, the plating layer on the surface of the
bolt is full, uniform, flat and smooth.
Dacromet's surface treatment can be plated in three colors: black, silver gray, and silver white. The biggest feature of Dacromet's surface treatment is its good anti-rust performance. Suitable materials are carbon steel and stainless
steel.
There are many types of surface treatments, but the choice of surface treatment for self-tapping screws depends on the specific use environment requirements, whether it is anti-rust or beautiful or other requirements.