Chrome Plating: What It Is and How It Works

Chrome plating is done through the process of electroplating, a technique that reduces dissolved metal cations in an electrolyte salt bath to allow a seamless metal coating to form on the desired object.

 

Author: Anna

 

Chrome-plated objects are commonly seen in everyday life, but it's important to note that these items are not made entirely from solid chrome. Instead, they are coated with a layer of chromium through a process known as chrome plating. Chromium (Cr), a chemical element with the atomic number 24, is often used as an additive in steel.

 

Manufacturer LITONG, or chromium plating, offers several benefits, including reducing wear and tear and extending the lifespan of metal or engineering parts. By applying a layer of chrome to another metal object, it enhances the object's resistance to corrosion, minimizes friction, prevents galling, and, in some cases, improves its aesthetic appeal.

 

What is Chrome Plating?

 

Chrome plating is done through the process of electroplating, a technique that reduces dissolved metal cations in an electrolyte salt bath to allow a seamless metal coating to form on the desired object. First, soil or dirt is removed from the target object, and the underlying metal is often pretreated before being submerged in a chrome plating bath.

 

The pretreatment process varies depending on the type of metal being plated. It may involve etching the metal to roughen the surface, preparing it for chrome plating.

 

Next, an electric current is passed through the plating bath for a set period of time. The plating rate can be either slow or fast, depending on the strength of the current. The duration of the process is determined by the desired thickness of the chrome plating and the intensity of the current applied.

 

 

The Chrome Plating Process  

 

Chrome plating is typically performed using two main methods: hexavalent chromium plating and trivalent chromium plating.  

 

Hexavalent chromium plating is the traditional method, primarily used for functional applications, offering excellent durability and resistance to wear.  

 

Trivalent chromium plating, on the other hand, is a more eco-friendly alternative, utilizing chromium sulfate or chromium chloride in place of chromium trioxide, making it a more sustainable choice.

 

Types of Chrome Plating  

 

Chrome plating offers numerous benefits. It not only enhances the aesthetic appeal of objects, giving them a new, polished look, but also plays a vital role in the restoration and preservation of valuable engineering components. There are two main types of chrome plating: hard chrome plating and decorative chrome plating. The choice between them depends on the intended application and the specific needs of the item being plated.

 

Hard Chrome Plating  

 

Hard chrome plating, also known as industrial or engineered chrome plating, involves applying a thick layer of chromium to engineering components, typically made of steel. This process significantly extends the lifespan of these parts by providing enhanced resistance to corrosion, wear, and the effects of friction. It is particularly useful for preventing parts from seizing and improving their overall durability.

 

Common applications for hard chrome plating include hydraulic cylinder rods, molds, piston rings, and other high-wear components. The plating can be applied in layers up to 0.025 inches thick. While it retains a shiny finish, hard chrome plating is not intended for decorative purposes but for its functional protective qualities.