Electroplating

The history of galvanising: where did we begin?

Electroplating was introduced at the end of the 18th century, when Luigi Galvani and Alessandro Volta created the connections between electricity and chemistry with their revolutionary innovations. Galvani’s research into the electrical stimulation of animal organs led to the discovery of a phenomenon that highlighted the relation between electricity and chemical reactions. Later, Volta’s innovation, the first electric power source, made possible the electrolytic experiments that provide the basis for electroplating. In the early 1800s, the first electroplating methods were already available, the first initial electrolytic plating methods to protect metal surfaces against corrosion.

The Industrial Revolution gave a big push to progress, especially in industries where metal protection was essential. The shipbuilding, general construction and rail freight industries were early to recognise the benefits of this coating method, which significantly increased the resistance of metals to the effects of weathering. The use of galvanised steel has resulted in products and structures having a longer durability, all in an affordable and effective way. Since then, galvanising has become an essential technology in many industries and has become basic to the sustainabilty of modern infrastructure.

Electroplating in practice: why is it relevant and how does it work?

The process of electroplating involves coating the surface of a metal material with a protective layer of another metal to preserve it from corrosion. It should be pointed out here that this is no defence against mechanical damage and physical environmental impact. The first step in the process is to ensure that the surface is thoroughly cleaned, as even the slightest dirt can prevent the coating from being applied. The clean surface is then placed in an electrolytic bath, which induces an electrochemical reaction. The electricity leads to the plating metal ions (such as zinc, chromium or nickel) being deposited on the surface of the base metal.

Electroplating not only offers durable protection, but can also be aesthetically beneficial. For example, chrome-plated parts give a bright, shiny surface that often improves the quality of the product (when metal surfaces are pre-polished to a mirror finish)

Zinc plating is particularly popular for protecting steel surfaces against rusting, while nickel, which forms a harder coating, provides hardness for protection against corrosion. However, please note that this is not the same as hard chromium!

Electroplating is also essential in the construction, automotive and engineering industries, where it reduces maintenance costs, improves durability and, not least, makes components more reliable.

It is important to note that different types of the technology are used depending on the requirements of the industrial sector. One of the most common methods is hot-dip galvanising, where the steel is dipped in a hot zinc bath to coat it with a thick, corrosion-resistant layer. Electrolytic galvanising, on the other hand, produces a more precise and thinner coating, which is used for finer workpieces.

How it works on different surfaces: applications and processes?

As mentioned in the previous sections, the use of electroplating on a variety of metal surfaces allows the process to meet the specific requirements of almost any sector. The type of process used, however, depends highly on the material or the components on which the coating is intended to be applied. In the case of steel, zinc plating is usually preferred, as this metal offers excellent protection against rust and a long lifetime. Structural steel components, such as building support girders or automotive parts, are therefore resistant to corrosion.

Nickel and chromium coatings are more commonly used on metal surfaces where durability is important as well as aesthetic appearance. Parts of electronic devices and precision engineering equipment are often coated in this way, because nickel and chrome coatings not only provide protection, but also a mirror-finish aesthetic surface, when they are preceded by the polishing mentioned above. Chrome plating is especially popular on decorative parts such as vehicle ornaments or even metal parts of household appliances and furniture.

Although there aren’t really any companies in Hungary that use this rare, specialised technology (neither do we), some electroplating techniques are used on plastic surfaces. Plastics usually require a preliminary layer of metal plating, which is then coated with a metallic coating. This method is particularly popular in the automotive and electronics industries, where plastic components are given an aesthetic, metallic appearance while maintaining the lightness of the material.

Finally, it is worth mentioning that special processes have been developed for materials exposed to extreme environmental conditions, such as structures used in a sea environment. In particular, it is important to use thicker and more corrosion-resistant coatings to provide long-term protection against seawater and constant wetting. Electroplating techniques applied to different surfaces thus add significantly to the durability and resistance of the products.

Current situation and future perspectives

Electroplating is still developing dynamically, as new technologies and materials are introduced in the industry. Today, there is an increasing emphasis on sustainable and environmentally friendly methods. One trend is to reduce chemical and energy consumption to minimise the environmental impact of the process. In addition, modern electroplating equipment now uses automated and digitally controlled systems that enable precision control and more efficient operation. This allows the process to be faster, more cost-effective and fault-less, reducing the need for human interaction.

The future leads to digitisation and the development of new materials. More and more research is being pursued to develop special coatings that further increase the resistance of the surface, for example to chemicals, salt environments or extreme temperatures. In the future, of course, nanotechnology will also play a role, where ultra-fine coatings can be applied not only to metal surfaces but also to a wide range of other materials.

All in all, electroplating is one of the most important protection technologies which contributes to the durability and safety of industrial and infrastructure developments. As the industry evolves, electroplating also meets new challenges, which can be answered by innovative solutions and continuous research and development. By developing sustainable, long-lasting and high quality coatings, this technology continues to play an irreplaceable role in the modern world.