Chrome Plating: What It Is and How It Works

Chrome Plating: What It Is and How It Works
Posted on March 20th, 2020 at 5:15 PM

We’ve all heard of chrome-plated objects. This typically means that these objects are not made entirely of solid chrome, but instead are coated in a layer of chrome through a process known as chrome plating. Chrome plating is the process of applying chromium to another metal object. Chromium is the chemical element (Cr) and atomic number 24, and is an additive in steel.

Chrome plating, or chromium plating, helps minimize wear and tear, as well as increase the lifespan of metal or engineering parts. By adding a layer of chrome to another object, it can improve the object’s resistance to corrosion, reduce friction, prevent galling, and in certain instances, enhance its appearance.

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. Soil or dirt is first removed from the desired object and often, the underlying metal is pretreated before being placed into a chrome plating vat.

Depending on the type of metal being plated, the process requires different pretreatments to etch the metal for specific metal types to roughen surfaces and prepare the metal for chrome plating.

An electric current is then run through the plating bath for a specific amount of time. Metal objects can be plated at a slow rate or a fast rate depending on the current. The amount of time required varies based on the thickness of the chrome plating needed and the current applied.

The Chrome Plating Process

Chrome plating is offered through two main processes: hexavalent chromium plating and trivalent chromium plating.

Hexavalent chromium plating is a traditional form of chrome plating and is mostly used for functional purposes.

Trivalent chromium plating is the eco-friendly solution to the traditional chrome plating option and uses chromium sulfate or chromium chloride as key ingredients in replacement of chromium trioxide.

Types of Chrome Plating

There are many advantages to chrome plating. Not only does it make objects look new and aesthetically pleasing, but it is also highly useful in restorative work and preservation of expensive engineering parts. There are two types of chrome plating, hard chrome plating and decorative chrome plating, and the type of chrome plating used is highly dependent on what it is needed for.

Hard Chrome Plating

Hard chrome plating, also known as industrial or engineered chrome plating, is a type of chrome plating that provides a very heavy coat of chromium on engineering parts that are typically made of steel. This helps preserve the lifespan of the parts and can provide high resistance to corrosion and wear of expensive metal objects. It is also used to prevent seizing of parts and increase durability.

Examples of parts that require hard chrome finishes include hydraulic cylinder rods, molds, piston rings, and more. Hard chrome plating coats layers of chrome up to 0.025 of an inch in thickness and while it still maintains its shiny appearance, it is not used for aesthetic or decorative purposes.

Erie Hard Chrome Can Help

Chrome plating is not an easy process of dipping objects into a bath of chromium. The process requires careful monitoring of temperatures and substances while slowly coating objects with layers of chromium. The process is a tedious one that utilizes highly toxic chemicals and should always be done by a professional. Let Erie Hard Chrome take the hard work off of your shoulders. Call today to learn more about what we offer or to request a free quote.

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