Electroplating treatments

What are electroplating treatments?

Let’s see what industrial electroplating treatments are, the methods underlying electrolytic plating and the greatest advantages and alternatives these treatments.
Electroplating is a very ancient technique. The first to historically hypothesize the effectiveness of electrolytic plating as a solution to make some materials more resistant to corrosion was the French engineer Stanislas Sorel in 1837.

His studies relied on a discovery made a century earlier by the chemist Melouin: the possibility of protecting steel from rust due to a zinc coating. His was more of an intuition. Melouin had in fact failed to explain the process behind what was later called galvanization (the name is due instead to Luigi Galvani, one of the first scientists to devote himself to electrical phenomena).

How does electroplating work? Techniques and effectiveness

Electroplating can basically be performed using three different techniques:

• • hot-dip plating treatment (the oldest electrolytic plating technique, the one patented by Sorel);
  • cold electroplating (i.e. electrolytic deposition);
  • hot-dip electroplating (i.e. immersion in a bath of molten zinc).

The effect is nearly the same. Why does it work? Through electroplating, zinc and steel come into contact and as an alloy, leading to a difference in electric potential. Should the zinc coating become scratched (even though it is very resistant), the above-mentioned difference in electric potential means the internal steel structure will remain intact because it is the zinc surface that corrodes.

With this premise, we have also explained the primary purpose of electroplating treatments: their clear protective properties. However, there are times when electrolytic plating is adopted for merely aesthetic purposes.

Pros and cons of electroplating and possible alternatives

Is such an old system like electrolytic plating still effective today? Yes! And it undoubtedly has the advantages that it is fast, easy to perform and inexpensive.

This does not mean that great steps forward have not been made in parallel, also due to the discovery of innovative and very high-performance materials such as fluoropolymers, which were still unknown in 1800. The discovery of the first fluorinated polymer, polytetrafluoroethylene (PTFE), dates to 1938.

This also was a chance discovery, to tell the truth. Roy J. Plunkett, an employee at the DuPont Jackson Laboratory in New Jersey (USA), was working on experiments on gaseous products when he observed the spontaneous polymerization of a gas into a solid mass. The properties of fluoropolymers are unique in terms of resistance to external aggression.

Today, electrolytic plating remains a recommended technique for inexpensive, effective solutions, and there are certainly no obstacles to its use for aesthetic coating. (Such is the case that although we strongly advise against improvising in this area, you can even find tutorials online for DIY electroplating, proving that it is not a particularly complex technique).

Teflon (PTFE), FEP and PFA coatings, for example, are highly recommended in the food and pharmaceutical sectors due to their non-toxicity.

Compared to electroplating, Teflon PTFE and FEP coatings, as well as VICOTE coatings, have a low environmental impact because they do not contain volatile organic compounds. This is why they are considered eco-friendly industrial coatings, an aspect to which more and more companies today are fortunately paying increasing attention.