Zinc plating is an essential treatment in the metallurgical industry. It protects metal components against corrosion, significantly extending their service life. This process involves applying a layer of zinc to the surface of parts made from metals such as steel, iron, or Zamak, creating an effective barrier against corrosive agents.
At Jegan, we apply electrolytic zinc plating to our Zamak components as part of our commitment to quality and durability. In this article, we detail the stages of the process, its main benefits, and its most common applications across industrial sectors.
What is zinc plating?
Zinc plating is a metal coating process that deposits a layer of zinc onto a metal part to protect it from oxidation. This layer acts as a physical barrier and provides cathodic protection, as the zinc oxidises preferentially over the base metal if the coating is damaged.
Several application techniques exist, such as hot-dip galvanising, mechanical plating, and electrolytic zinc plating. The latter, also known as electroplating, is especially valued for its precision, uniform coating, and surface finish, making it the preferred method for parts requiring aesthetic appeal or tight tolerances.
Stages of the Electrolytic Zinc Plating Process
Electrolytic zinc plating comprises several controlled stages that ensure a uniform, functional, and aesthetically suitable result:
Surface preparation
The first step involves preparing the component's surface through chemical cleaning processes. This includes degreasing, pickling, and rinsing to remove residues, oils, oxides, or any contaminants that might interfere with proper zinc adhesion. Effective cleaning is critical to ensuring a durable coating.
Electrolytic bath
Once clean, the component is placed in a bath containing a zinc salt solution (typically chlorides or sulphates) and connected to a direct current source. Under the influence of this current, zinc ions are deposited in a controlled manner onto the metal surface, forming a thin, uniform, and adherent layer.
Post-treatment and passivation
After the coating is applied, the components undergo passivation treatments to enhance resistance to white rust (zinc oxidation). Depending on the application, additional protective layers may be used, such as sealants, transparent lacquers, or coloured coatings that increase durability and improve the visual finish.
Main Advantages of Electrolytic Zinc Plating
Electrolytic zinc plating offers several advantages, making it an efficient and reliable option for protecting metal parts. One of its main advantages is its high corrosion resistance, as the zinc layer acts as a barrier that prevents direct contact between the base metal and external agents such as moisture, oxygen, or chemicals. Additionally, the process ensures a uniform and visually appealing finish, which is particularly useful in applications where appearance matters.
Another key advantage is the excellent adhesion that the zinc-coated surface offers for applying paints, lacquers, or other additional coatings, facilitating further treatments. The process is also known for its cost-effectiveness, as it allows for treating large volumes of components quickly and at relatively low cost. Furthermore, it is highly versatile, as it can be applied to parts of various shapes and sizes, including those with complex geometries or detailed features.
Applications of Zinc Plating Treatment
Zinc plating is widely used across various industrial sectors, thanks to its ability to protect metals without compromising their mechanical properties. In the automotive industry, for instance, it is used to coat screws, nuts, washers, and other components exposed to harsh environmental conditions, extending their lifespan and ensuring proper functionality.
In construction, zinc plating is applied to metal structures, tools, and fasteners, offering adequate protection against rust. It is also commonly used to manufacture household appliances and electronic equipment, where internal components must withstand humidity without deteriorating. Likewise, zinc plating is used in the furniture industry to protect and enhance the appearance of fittings, hinges, and other visible metal accessories. Finally, in the machinery industry, this treatment helps extend the service life of components subjected to friction, mechanical stress, or harsh environments, ensuring optimal performance under demanding conditions.
Jegan: Specialists in Zamak and High-Quality Finishes
At Jegan, we have been dedicated to manufacturing and finishing Zamak components for over five decades, offering complete technical solutions tailored to each client. We manage the entire process: from mould design to the final finish, including surface treatments such as zinc plating, painting, chrome plating, and nickel plating.
Our team combines experience, technology, and commitment to ensure quality at every project stage. We work with companies in demanding automotive, electronics, lighting, and construction sectors, adapting to mass production and specific requirements.
