Spraying (painting) and electroplating are two common surface treatment processes, which are widely used in different materials and different fields. These two processes have their own characteristics.
Electroplating vs Painting
Electroplating is the process of attaching a thin layer of one metal, such as chrome, iridize or zinc, to the surface of another base metal, such as aluminum. The plating is chemically bonded to the surface of the base metal through electric conduction. Electroplating should not be confused with anodizing, which involves bonding an additional layer of the same metal to the base product through the same electrochemical process.
Painting is more straightforward and most people are familiar with it. A primer is first applied to the base metal, followed by multiple layers of liquid paint and finally, a protective coating such as lacquer is added to protect the underlying paint.
Advantages and Drawbacks of Electroplating
Electroplating offers a much stronger finish than paint. Depending on the choice of metal used for electroplating, the object may have better resistance to chemical corrosion or increased physical durability. For example, zinc offers additional resistance to water damage, while chrome reduces the friction on the metal’s surface and tin can be used to join aluminum, which is commonly used in sheet metal manufacturing, to dissimilar materials. Certain finishing metals can also increase paint adhesion to metal parts as well.
Because electroplating chemically bonds the finish to the metal product itself, the coating expands and contracts at the same rate of the base metal itself, making it suitable for environments with drastic temperature fluctuations.
However, electroplating can be expensive and uneconomical, especially when parts are small. Furthermore, the advantages offered by electroplating may be excessive if the metal product is intended for a use that does not take full advantage of the benefits offered by the process.
Advantages and Drawbacks of Painting Sheet Metal
The most obvious advantage of painting is that fabricators have a much greater degree of control over how the finished product will look. Paint comes in just about any color imaginable, meaning that there are endless options for how the final product will look. Furthermore, company and product logos can also be added to the surface to further increase its cosmetic value.
Certain paints offer similar advantages to electroplating; some can increase the metal product’s resistance to chemical corrosion or physical damage, though not to the same degree as electroplating. Damage to specific areas of painted surfaces is easily repaired as paint can be applied quickly and easily to small areas of a product’s surface. Another advantage paint has over electroplating is that it can be applied to certain areas of a product’s surface if the entire product does not require finishing. Unlike electroplating, painting is not an “all or nothing” process.
Paint, however, is not as durable as electroplating. Furthermore, because paint is applied as liquid, it can take many applications to ensure a finish of even thickness and color.
Metal Spraying Offers the Following Advantages Over Electro-Plating
Adhesion is usually better Non-metallic substrates can be treated Engineering alloys can be applied as coatings Ceramic coatings can be applied Thicker deposits can be applied There is no risk of hydrogen embrittlement Deposition rates are higher There is no component size limitation Coatings can be applied on site There is no effluent disposal problem Jigs and fixtures do not corrode Complex chemical control techniques are not required
Chrome Plating vs. Spray Chrome
1. Electroplating, has several advantages. It can withstand extreme weather and temperatures and will not corrode or oxidize. It is easy to take care of and has a beautifully glossy finish. People are able to refurbish their damaged chrome-plated parts, saving them the expense of having to purchase new parts. When a part is stripped and then chrome plated, it will be restored to the same condition it was in when it was new.
There are several disadvantages to electroplating chrome onto the surface of an object. The chemicals that are used in the chrome-plating process are very toxic, so their use is heavily regulated by the government. It takes significantly more time than does spray-on chrome and is very expensive. Because the parts must be dipped in vats for the chroming process, people are also limited by the size of the part that they wish to chrome.
The Disadvantages of Chrome Plating include the following:
Non-uniform coating Hexavalent Chromium is a hazardous air pollutant Measuring surface tension is tedious and suffers from inaccuracy Corrosion resistance of thicker coatings is not quite as good Cost of the chemicals is greater Chrome plating process is hard to control
2. Spray-on chrome has numerous advantages. It is simpler to apply and can be done in a person’s own garage or shop. People do not have to send parts off, saving them time and money. Spray-on chrome is very versatile and is not limited by how large a part is that the person wants to spray chrome. It can be used on a broad variety of different materials, including glass, plastic, metal and wood. It is much less expensive and gives the same high-quality durable finish and gleam people obtain through electroplating.
The advantages of PChrome include all of the following:
Durability as good as chrome plating Bonds to the substrate just as well Highly weather-, scuffs-, and salt-resistant Highly reflective A greener choice than traditional chrome plating Cheaper cost Can be used regardless of the size of the part Can be used on-site Fewer steps in the process Thicker coatings Choice of materials Reduced turnaround time Fewer health and safety concerns
Which Option is Best For You?
Electroplating and painting(spraying) each offer unique advantages for finishing a sheet metal product. Ultimately, deciding on which finishing option is best for you depends on the intended use of your product. It is important that you consider all factors and the advantages and drawbacks of each before making a final decision.