Guide To Electroplating: Process, Techniques, Applications

Electroplating is a widely utilized method for enhancing and polishing metal that finds application in many different sectors. Even so, very few people outside the business are aware of what electroplating is or how it operates despite its widespread use. You should understand how electroplating operates and what material and process options are available to you if you're thinking about using it in your following production process.

ELECTROPLATING: WHAT IS IT?

Another name for electroplating is electrodeposition. The procedure includes employing an electric current to deposit material, as the name would imply. The substrate, a workpiece, has a thin layer of metal deposited on its surface as a result of this procedure. The primary purpose of electroplating is to alter an object's physical characteristics. This method can be applied to things to offer them more thickness, wear resistance, corrosion protection, or aesthetic appeal.

Electroplating is a centuries-old procedure despite the appearance of modern technology. Early 18th-century experiments were the first to use electroplating, and Brugnatelli formalized the procedure in the first part of the 19th century. Following Brugnatelli's research, Europe created and embraced the electroplating method. The electroplating technique developed to meet demand as manufacturing methods expanded during the following two centuries as a result of the Industrial Revolution and two world wars, leading to the procedure that Sharretts Plating Company uses today.

PROCESS OF ELECTROPLATING

Metal is dissolved and then deposited onto a surface using an electric current in the electroplating process. The four main parts of the procedure are as follows:

• ANODE - The metal that will make up the plating is the anode, or positively charged electrode, in the circuit.
• CATHODE - The component in an electroplating circuit that has to be plated is the cathode. Another name for it is the substrate. This component serves as the circuit's negatively charged anode.
• SOLUTION - An electrolytic solution is used for the electrodeposition reaction. To help with electrical flow, this solution includes one or more metal salts, typically copper sulfate.
• ENERGY SUPPLY - Using a power source, current is added to the circuit. By supplying the anode with a current, this power source gives the system electricity.

Direct current (DC) is supplied to the anode by the power source once the anode and cathode are connected and placed in solution. As a result of the metal being oxidized by this current, metal atoms might dissolve as positive ions in the electrolyte solution. The metal ions are subsequently drawn to the negatively charged substrate by the current, where they deposit a thin layer of metal onto the object.

Take the technique of plating gold onto metal jewelry as an illustration. In the circuit, the metal jewelry serves as the cathode, and the gold-plated metal as the anode. When DC electricity is applied to the gold, which dissolves in solution, both are submerged in it. A layer of gold is subsequently formed on the base metal jewelry by the atoms of dissolved gold adhering to its surface.

Three things can affect how well the plating is done, even though this procedure is consistent. These elements consist of the following:

• BATH CONDITIONS - The electroplating process's efficiency is affected by the bath's chemical makeup and temperature.
• PART PLACEMENT - The anode's position in relation to the cathode is crucial because it determines how far the dissolved metal must travel in order to plate the substrate.
• ELECTRICAL CURRENT - The effectiveness of the electroplating process depends on the voltage level of the electrical current and the application duration.

WHICH METALS ARE APPLIED IN THE PROCESS OF ELECTROPLATING?

Electroplating can be carried out using single metals or other alloy combinations that provide value to the process. Among the metals that are most frequently utilized for electroplating are:

• COPPER - Due to its heat resistance and conductivity, copper is frequently utilized. It's also frequently applied to enhance material adhesion between layers.
• ZINC - Zinc has a strong resistance to corrosion. To improve this quality, zinc is frequently alloyed with other metals. Zinc, for instance, is very resistant to air corrosion when alloyed with nickel.
• TIN - This brilliant, matte metal is both environmentally benign and very solderable. It also resists corrosion. In addition, it is less expensive than other metals.
• NICKEL - Heat treatment can be used to enhance the metal's exceptional wear resistance. Because of their elemental resistance, hardness, and conductivity, alloys are also critical. In addition, electroless nickel plating is prized for its hardness, minimal friction, magnetism, and resistance to corrosion.
• GOLD - This valuable metal is prized for its conductivity and visual attractiveness and has a strong resistance to corrosion, tarnish, and wear.
• SILVER - Although it is not as resistant to corrosion as gold is, silver is still very ductile and malleable, has good resistance to wear from the touch, and has superb beauty. In situations where thermal and electrical conductivity are required, it can also be used as a substitute for gold.
• PALLADIUM - Because of its hardness, resistance to corrosion, and lovely finish, this bright metal is frequently employed in place of gold or platinum. This metal acquires outstanding hardness and plating quality when alloyed with nickel.

The cost, the type of substrate, and the intended outcome are essential considerations when choosing the suitable electroplating material for your application. You may also wonder about the essential considerations for metal finishing. Some of the factors that affect the finish quality of your surface include cutting-edge geometry accuracy, tool wear, built-up edges, and machine tool accuracy.

TECHNIQUES OF ELECTROPLATING

There are numerous plating methods available, and there are applications for every one of them. A more thorough description of a few of these electroplating techniques can be found below.

1. BARREL PLATING

Large batches of tiny parts can be plated using the barrel plating technique. Parts are inserted into a barrel that has an electrolyte solution inside it during this operation. As the barrel rotates, the electroplating process continues, agitating the components to achieve uniformly even finishes. Small, robust parts are ideal candidates for barrel plating, which is an affordable, effective, and adaptable option.

2. RACK ELECTROPLATING

If you need to plate big batches of parts, rack, or wire, plating is an excellent solution. This method puts the components in direct contact with the electrical power source by arranging them on a wire rack. This solution is best for more delicate items that cannot be barrel-plated, even if it is more expensive. It's crucial to remember that parts with irregular shapes or those that are electrically sensitive are more challenging to rack plates.

3. ELECTROLESS PLATING

Similar to electrodeposition, electroless plating, often referred to as autocatalytic plating, does not involve physically applying electricity to the part. Rather than utilizing an electrical process, the plating metal is dissolved and deposited through a chemical process. This alternative is less efficient and more expensive than the other two, even if it can be helpful for parts that are incompatible with electrical currents.

Although these techniques differ in how they achieve electrodeposition, they all follow the same fundamental ideas.

APPLICATIONS OF ELECTROPLATING

Although electroplating is frequently employed in a variety of sectors to enhance a base material's aesthetic appeal, it also serves a number of additional functions. Among these applications are the following:

• INCREASE THICKNESS - By gradually applying thin layers, electroplating is frequently employed to increase a substrate's thickness.
• SHIELD THE SUBSTRATE - Layers electroplated with metal act as sacrificial coatings. This implies that the plated layer degrades before the base material does in an adverse environment, shielding the substrate from harm.
• GIVE A SURFACE QUALITY - Electroplated Substrates can take advantage of the characteristics of the metals they are plated with. Certain metals, for instance, can lessen friction, enhance electrical conductivity, prevent corrosion, or prepare a surface for better paint adhesion. Different metals impart various qualities.
• ENHANCE APPEARANCE - Electroplating is, of course, also frequently utilized to enhance a substrate's visual appeal. This could be as simple as applying a layer to enhance surface quality and uniformity or as complex as plating the substrate with an aesthetically beautiful metal.

ADVANTAGES OF ELECTROPLATING

Components can benefit from a number of electroplating processes. The following are a few advantages of electroplating precisely:

• PROTECTIVE BARRIER - The substrate is shielded from the elements by the barrier that electroplating forms on it. This barrier may occasionally be able to prevent atmospheric deterioration. This feature especially helps components since it makes them more resilient to severe environments, requiring fewer replacements over time.
• ENHANCED APPEARANCE - To make exterior components more shiny and eye-catching, tiny coats of precious metal are frequently plated over them. Because this plating adds visual appeal without breaking the bank, beautiful parts can be offered for less money. Furthermore, electroplating is frequently used to keep cutlery from tarnishing, enhancing its durability and long-term aesthetic appeal.
• ELECTRICAL CONDUCTIVITY - Copper and silver plating contribute to increased electrical conductivity in parts, providing an economical and effective way to enhance conductivity in electrical and electronic components.
• HEAT RESISTANCE - A number of metals, such as zinc-nickel and gold, can withstand high temperatures, which helps the substrate withstand heat-related damage. The lifetime of the plated parts may thus be extended as a result.
• INCREASED HARDNESS - Electroplating is frequently used to increase the strength and resilience of substrate materials, reducing their susceptibility to deterioration as a result of misuse or stress. This characteristic may prolong the life of plated components and lessen the need for replacement.

Certain benefits are exclusive to certain metals. For instance, nickel plating can assist in lowering friction, which lessens wear and tear and extends the life of parts. Conversely, the use of zinc-nickel alloys helps avoid the production of sharp protrusions during the manufacturing process, which may cause damage to parts. In many applications, copper is also mainly employed as an undercoating because it helps other metal coatings adhere to the part, improving the item's surface quality.

INDUSTRIES WHICH USE ELECTROPLATING

Electroplating provides solutions for any type of corrosion protection, durability enhancement, or higher electrical conductivity that your business may require. Because of this, electroplating is frequently utilized in many different sectors. Some of the industries that SPC supports are listed below, along with how they use electroplating:

AUTOMOTIVE INDUSTRY

In the automotive industry, plating is frequently utilized to stop corrosion in challenging environments. While electroless nickel plating is a fantastic substitute for chrome on catalytic converters and plastic parts, zinc-nickel plating treatments aid in the prevention of rust formation.

ELECTRONICS INDUSTRY

Due to the conductivity of gold plating, semiconductors, and connections are frequently plated by electronics businesses. In this industry, gold is also sought after because of its resistance to corrosion. In this industry, copper plating is another often utilized metal that is substituted for gold when conductivity is the primary concern. Palladium alloys are also frequently applied to electronic components and equipment as protective coatings.

MEDICAL INDUSTRY

Metal electroplating is frequently used in the medical equipment industry to enhance the biocompatibility of components, particularly implants. Because of their biocompatibility, resistance to corrosion, hardness, and resistance to wear, gold, silver, and titanium are frequently utilized in this field. These qualities are crucial for implant and joint replacement applications.

AEROSPACE INDUSTRY

Because titanium has a high strength-to-weight ratio, it is widely used in the manufacture of airplanes. In this business, nickel plating is also frequently used to prevent corrosion and wear, and copper is utilized to increase heat resistance.

OIL AND GAS INDUSTRY

Because of the nature of petrochemicals, corrosion protection is one of the industry's top concerns. Electroless nickel plating is frequently utilized in this sector to prolong the life of parts by preventing corrosion on pipes and other components.

Electroplating is used in a wide range of different industries, including the military, defense, and gun industries. All of these industries prefer electroplating due to its practicality, affordability, and adaptability.

CONCLUSION

The efficiency of your business depends on identifying optimal production solutions. For many applications, electroplating is a cost-effective and functionally advantageous solution; however, to fully realize these advantages, you must work with an appropriate plating business.