Two common types of zinc electroplating solutions are acid zinc and alkaline zinc, each of which offers certain advantages and disadvantages. Following are some of the prominent benefits of using the acid variety:
The Brightness of Acid Zinc Plating
One prominent advantage of using an acid zinc plating solution is the brightness you achieve, which often creates a “decorative chrome” look. While many professionals attempt to achieve this brightness with different types of alkaline solutions, nothing matches the decorative brightness of acid zinc solutions.
The Speed of Acid Zinc Plating
Another benefit of using an acid zinc plating solution is the speed it offers, as acid zinc has a plating efficiency of almost 100 percent and can reach a given thickness in a high-current-density area more quickly than any other solution can. For example, it is possible to accomplish 8 microns in a high-current density area in 10 minutes with rack plating, whereas such a process would take about 20 minutes with alkaline zinc.
However, keep in mind that speed is different from throughput, the amount of product or surface area processed in a certain amount of time. Acid zinc has significant thickness-distribution issues and can take longer to reach certain thicknesses in low-current density areas than alkaline zinc does.
The Ductility of Acid Zinc Plating
For parts that you plan to post-form—bend or shape after zinc plating—acid zinc is much more ductile and therefore less likely to crack and break off when you create these parts. However, acid zinc plating is not as ductile as cyanide zinc is.
Acid Zinc Plating and Cast Iron
One final advantage that acid zinc plating offers over its alkaline counterpart is the ability to plate cast iron, which is extremely difficult to accomplish with an alkaline zinc solution. One example of cast iron parts that can benefit from zinc plating is brake calipers.
When determining whether acid zinc plating is the best solution to use in your application, it can help to consider its advantages, which include brightness, speed, ductility, and the ability to plate cast iron. For more details about acid zinc plating, consult our knowledge base at www.thefinishingexperts.com.