It has only been about a half a century that non-cyanide zinc alkaline plating was available. In the early days of the development of the technology, there were some issues, particularly with the disposal of the solutions, but this has long been an issue that the industry has responded to and corrected.
Through the use of the technology available today, the use of cyanide is largely eliminated, and the systems are designed to provide a highly corrosion resistant coating on all types of complex surfaces.
With the use of zinc alkaline plating, there is also a very thin layer deposited on the surface, eliminating the thick layers of zinc that were also a problem in the past. In the actual process of the plating the zinc bonds to the surface of the metal in a layer that cannot be removed. This layer is extremely corrosion resistant with regards to all types of environmental exposures.
The Advantages
Depending on the specific component, the surface film will be slightly different in color. It will always have the bright, traditional zinc color but it will be slightly more opaque or pearl in look than some of the other metal finishing choices.
The look of the zinc alkaline plating is very fine grained, which means that it blends perfectly with the metal to create an aesthetically pleasing finished surface. It can also be further color treated, which may be an important consideration for OEM companies and for specific parts and components.
The central factor for the use of non-cyanide zinc plating is really the ability to apply only the thinnest possible layer. It can be plated onto any surface including threads and in cavities, making it an ideal process even for the most complex types of shapes and components.
Another critical difference to this plating option is the self-healing ability. This will help to mitigate any damage to the surface of the metal even after the plating has been completed. It is important to realize that the self-healing does take time, but it will repopulate the surface of the metal with the film with minor scrapes, abrasions and exposure to specific types of chemicals.
With zinc plating an effective, tight tolerance type of film can be applied quickly, effectively and in a zero-stress type of deposit. New formulations also prevent blistering after application due to the presence of the electrolyte.
