What is the Difference Between Chrome and Nickel Plating

The main difference between chrome and nickel plating is that nickel plating is less resistant to abrasion than chrome plating.

Electroplating is a process that involves depositing a thin layer of metal onto the surface of another material through an electrochemical reaction. Electroplating is used for various purposes, such as enhancing an object’s visual appeal, offering corrosion protection, improving wear resistance, boosting hardness, and aiding in soldering or brazing processes. Chrome and nickel plating are electroplating techniques used to deposit thin layers of chromium and nickel onto metal surfaces, respectively.

Key Areas Covered

1. What is Chrome Plating
      – Definition, Features
2. What is Nickel Plating
     – Definition, Features
3. Similarities Between Chrome and Nickel Plating
      – Outline of Common Features
4. Difference Between Chrome and Nickel Plating
      – Comparison of Key Differences

Key Terms

Chrome Plating, Nickel Plating

What is Chrome Plating

Chrome plating, also referred to as chromium plating, involves electroplating a thin layer of chromium onto a metal object, commonly known as chroming, to achieve decorative, corrosion-resistant, easy-to-clean, or increased hardness properties; occasionally, nickel might be used as a cost-effective alternative for aesthetic purposes.

The chrome plating method offers two processes: hexavalent chromium and trivalent chromium.

The hexavalent chromium process, frequently utilized for functional purposes, is notably toxic and recognized as a human carcinogen. The waste generated by this process is hazardous and requires proper treatment before disposal.

On the other hand, trivalent chromium plating, employing chromium sulfate or chromium chloride, provides a more environmentally friendly alternative. It can replace hexavalent chromium plating in specific applications and thicknesses, offering a less toxic option. However, the usage and disposal of waste from trivalent chromium plating are also rigorously regulated to ensure environmental safety.

What is Nickel Plating

Nickel plating, also known as nickel electroplating, is a method used to apply a layer of nickel onto the surface of metal parts. The process involves several steps to ensure a successful outcome. Before the plating process begins, the metal parts must undergo thorough cleaning to remove any dirt or damage. This preparation phase involves various techniques such as heating, cleaning, and masking, all of which contribute to ensuring the parts are ready for plating and remain undamaged throughout the process.

Once the parts are adequately prepared, they are immersed in a liquid solution known as an electrolyte. This solution plays a critical role in the plating process. Within the electrolyte, the metal object becomes the cathode—the negatively charged electrode. Simultaneously, a piece of nickel, known as the anode, dissolves in the electrolyte, releasing nickel ions (Ni2+). These ions traverse the solution and adhere to the cathode, a mechanism reminiscent of other electroplating processes where electricity is employed to coat objects.

The anode’s efficiency in dissolving nickel is typically very high, reaching nearly 100%. However, occasional problems may hinder its effectiveness. Meanwhile, the cathode efficiency, the rate at which nickel ions adhere to the cathode, is slightly lower, ranging from 90% to 97%. This discrepancy in efficiency leads to a gradual increase in the concentration of nickel within the solution, causing the pH level to rise.

The entire process spans a variable timeframe, typically taking minutes to hours. The duration depends on factors such as the desired thickness of the nickel coating and the strength of the electric current used. Nickel plating can be applied to various metals, including steel, copper, aluminum, zinc, brass, bronze, and iron, to enhance their properties, such as corrosion resistance, wear resistance, conductivity, or aesthetics.

Similarities Between Chrome and Nickel Plating

• Chrome and nickel plating result in a shiny, metallic finish that enhances the visual appeal of the plated object.
• Both plating methods provide a protective layer that enhances the object’s resistance to corrosion, helping to extend its lifespan.
• Both methods contribute to a smooth and even surface texture, which can improve the object’s tactile qualities and overall quality.

Difference Between Chrome and Nickel Plating

Definition

Chrome plating is the electroplating process of depositing a layer of chromium onto a metal object, often for decorative and corrosion-resistant purposes. Nickel plating is the electroplating process of depositing a layer of nickel onto a metal object to enhance properties like corrosion resistance, wear resistance, and conductivity.

Color Stability   

Chrome maintains its reflective quality over time and doesn’t change color, making it superior to silver and nickel. However, nickel plating may exhibit a slight yellowish tint over time.

Uniformity         

Moreover, chrome plating offers slightly better uniformity compared to nickel plating.

Corrosion and Abrasion Resistance          

Chrome plating demonstrates strong resistance to both corrosion and abrasion, surpassing nickel plating in abrasion resistance. Nickel plating is less resistant to abrasion but still provides good corrosion resistance.

Cost      

Nickel plating is more affordable than chrome plating.

Appearance       

Chrome plating generally maintains a bright white appearance, while nickel plating has a slightly yellowish tint but can vary based on the specific plating process.

Removing

Generally, chrome plating is harder to remove compared to nickel plating due to chrome’s exceptional hardness and durability.

Conclusion

Chrome plating demonstrates strong resistance to both corrosion and abrasion, but nickel plating is less resistant to abrasion but still provides good corrosion resistance. Thus, this is the main difference between chrome and nickel plating. In addition, chrome plating offers slightly better uniformity compared to nickel plating. However, nickel plating is more affordable than chrome plating.

Reference:

1. “Nickel Plating.” Wikipedia. Wikipedia Foundation. 
2. “The Best Guide of Chrome Plating” LEADRP.

Image Courtesy:

1. “Motorcycle Reflections bw edit” By Atoma – Own work (CC BY 2.5) via Commons Wikimedia
2. “Vintage Ever-Ready Cow Catcher Nickel-Plated Safety Razor, Made In USA, Circa 1914 (27711869128)” By Joe Haupt from USA – (CC BY-SA 2.0) via Commons Wikimedia