Fastener surface treatment, according to their product requirements, there are many surface treatment methods and processing technology. According to the surface treatment methods can be divided into many, such as painting, electroplating, electroless plating, vacuum coating, dip plating, anodizing, sand blasting, coating, vapor deposition, carburizing, nitriding, surface hardening; More advanced, there can be a lot of methods, physical, chemical, electrical processing, mechanical, metallurgical and so on.
Common surface treatment methods are the following:
Electroplating: The electroplated part is immersed in an aqueous solution containing the metal compound to be deposited, and the electroplating metal is precipitated and deposited on the part through the plating solution. General plating with galvanized, copper, nickel, chromium, copper-nickel alloy, and sometimes will be black, phosphating, etc. also included. Electroplating easy to produce hydrogen embrittlement, the mechanical strength of the workpiece. Hot-dip galvanizing: Completed by plating the molten steel with a carbon steel part immersion temperature of about 510 ° C. As a result, the iron-zinc alloy on the surface of the steel gradually becomes a passivated zinc on the outer surface of the product. However, due to hot plating due to high temperature, steel is easy to produce high temperature annealing adverse effects.
Mechanical plating: mechanical plating is the activator, metal powder, the impact medium (glass beads) and a certain amount of water mixed into the slurry, together with the workpiece into the drum, by means of the rotation of the roller generated by the role of mechanical energy in the activator And the impact medium (glass beads) mechanical collision under the joint action, at room temperature in the iron-based surface gradually formed zinc coating process.
Dacromet: The following focuses on the advantages of surface treatment. Zinc chrome film (Dacromet) corrosion mechanism Description: Zinc chrome film (Dacromet) coating process is a new surface treatment technology, also known as Dacromet, Duckle, Duck rust, zinc chrome film (Dacromet), Duckman and so on.
As a green plating process, zinc chrome film (Dacromet) process using a closed-loop approach, in the pre-treatment: in addition to the oil and dust with a special equipment collection and treatment; in the coating, curing, there is no traditional plating The process of acid, alkali, chromium and other heavy metal sewage problems, resulting only from the coating evaporated from the water vapor, the determination, does not contain the provisions of the state control of harmful substances. Zinc chrome film (Dacromet) coating was matte silver gray, can be re-painted on the above.
