For those types of applications where parts will be exposed to extremely corrosive environments, or will be used in environments where contact with corrosive materials is ongoing, zinc iron plating offers the ultimate in protection.
The combination of zinc and iron in the plating makes the surface much more corrosion resistant than zinc plating without the iron component. Typically the deposits with this type of plating contain less than 1% by weight of iron, with most processes using a 0.4 to 0.8% iron content by weight. The concentration of iron in the plating bath can be managed through the use of specific additives to the process.
This combination of zinc and iron produces a very fine grained surface that is very compatible with further finishing with a trivalent passivate. This process forms an additional hard surface film on the zinc iron plating adding superior durability. It is also naturally uniformly bright, and it will be burn-free, leaving a very smooth and aesthetically improved final look.
For large run productions and extensive plating requirements, the use of zinc iron over other finishing and coating options provides a very economical option. It is often lower cost that zinc plating alone and it will offer up to 50% extension in the corrosion resistance.
For OEM parts manufacturers this is a real advantage. Not only is it lower cost to produce the original parts, but the parts themselves will last longer. This boosts the life cycle of the parts and increases the value of your products over the competition.
Ease of Processing
There are some important technical specializations that need to be closely adhered to for providing uniform deposits of zinc iron. Metal finishing companies offering the option for zinc iron plating are typically specialized companies that are using the latest in technology and plating equipment to complete the process.
It is important for the metal finishing company to use specific controls, including with the current density, to ensure uniform distribution of the iron content across the surface of the component. With technology and the latest in equipment as well as experience in this plating process, tight tolerances can be maintained throughout production, which is essential for a uniform final product.
With these companies, additional additives will be used in the zinc iron combination. The purpose of these additions is to create the natural bright finish and also to enhance the fine grain that is a hallmark of the process.