Electroplating - EvoSteel

Electroplating is a surface coating technique used in the manufacturing industry. This method uses electric current to apply a metallic coating to the surface of a material. Electroplating is an electrochemical process where the surface of one metal is coated by combining ions of another metal through an electrochemical reaction.

In recent years, the electroplating process has made significant advances. These advances have made more accurate and precise coating processes possible. It has also expanded the coating of different materials. Now, metallic surfaces, plastics, ceramics, and even composite materials can be electroplated. This has widened the range of materials and allowed electroplating to be used in various industries.

Electroplating is the process of depositing a thin layer of metal atoms on the surface of a material by electrolysis. In this process, the added metal called the deposition metal, forms a layer on top of the workpiece, known as the substrate material. By depositing the desired metal in layers to improve the physical, mechanical, and chemical properties of the substrate material, improvements in the material’s properties, such as durability, thermal and electrical conductivity, wear, and corrosion resistance, can be achieved.

These enhancements combine various metals to offer properties better suited to different applications. For example, a steel material can be electroplated with zinc to improve its corrosion resistance, making it more durable and long-lasting. Likewise, it is possible to apply different metals, such as copper plating, to improve the thermal conductivity of a material’s surface. These methods can be customized according to different industrial needs, thus ensuring that the material has the desired properties.

Electroplating operates as a process based on the electrolytic cell principle.

In this process, two metal rods are placed in an electrolyte. When these rods are connected to opposite battery or power supply terminals, they act as electrodes with the potential difference created by the electric current. This current causes the electrolyte solution to dissociate into metal ions, and positively charged metal ions accumulate on the negative electrode (cathode).

Positively charged ions are part of the electrolyte, and their concentration decreases as they accumulate at the cathode. We can create a source on the anode side by choosing a suitable element to replenish the concentration of positive ions.

For example, brass is used as a substrate for plating copper. When connected to the negative terminal, this brass acts as a cathode. By using an electrolyte, such as copper sulfate solution, we give positive copper ions due to the breakdown. Copper is used as the anode to replenish the positive ions of the electrolyte.

In this process, we can vary the process parameters to control many factors such as plate thickness, metal deposition rate, surface finish, color, etc. For example, using pure copper sheets provides a more aesthetic appearance than regular copper rods. With electroplating, the material can be coated with one or more metals.

The electroplating process allows different coating combinations to be achieved using various metals. The most commonly preferred metals for electroplating are:

Copper: Widely used for its conductivity and resistance to heat. It is also preferred to increase adhesion between materials.

Zinc: Known for its corrosion resistance. It is often alloyed with other metals to improve this property further. For example, zinc-nickel alloys can be resistant to atmospheric corrosion.

Tin: It has good soldering properties and is environmentally friendly. In addition to being resistant to corrosion, it is also cost-effective.

Nickel: Wear resistance can be improved by heat treatment. Its alloys offer different properties and provide resistance, hardness, and conductivity. It is also resistant to corrosion.

Gold: Known for its high corrosion and wear resistance. It is also preferred for its conductivity and aesthetic appeal.

Silver: Although not as resistant to corrosion as gold, it is notable for its ductility and malleability. It has heat and electrical conductivity.

Palladium: Often preferred over gold or platinum. Alloyed with nickel, it can offer excellent hardness and plating quality.

Pre-Process:
The pretreatment process consists of alkaline cleaning, acidic cleaning and electrolytic cleaning steps.

Covering:
Zinc nickel plating is an electrolytically applied process. The cathode (-pole) is connected to the material to be coated, the anode (+pole) end is connected to the sheet plates used to complete the circuit, and the coating is made under current with rectifiers.

Passivation:
Passivation applied on Zinc Nickel coating can increase corrosion resistance.

Top Lacquer:
Different top lacquer applications applied on the coating allow the corrosion resistance to be increased and the friction coefficient to be adjusted depending on the mounting conditions.