The right metal finishing technique can make a metal product or component perform even better. But with so many different techniques out there, how do you know which one will work best for your needs?
Understanding the importance of metal finishing and knowing some of the popular surface finishing methods, you’ll be better equipped to choose the most suitable option. A carefully selected finish can significantly impact both the appearance and durability of your product, helping it meet the specific requirements of its application.
Some of the most popular metal finishes include:
The technological importance of metal finishing is both functional and aesthetic. The most common reasons for specifying industrial metal finishing include:
Look at the list above. Do one or more of these qualities take priority in your current metal product design? That will probably determine which finishing process (or processes) you should specify.
Let’s look a little closer at each:
What is electroplating? This involves depositing a metal or alloy onto the surface of an object via a solution. The solution contains dissolved ions of both the deposited metal and the substrate (original underlying metal).
If electroplating sounds complicated, it's because it is — and because of how complicated it is and how difficult it can be to master the process, it's a finishing technique that can come with a hefty price tag compared to others.
Benefits of electroplating:
The benefits of electroplating are plentiful, and include superior corrosion protection and tarnish protection. You can add a non-corrosive metal over a cheaper, corrosive one to keep products such as appliances from deteriorating.
But it’s especially popular for its decorative value.
It may seem financially impossible for your design to incorporate rare and/or expensive metals like:
Through electroplating, your manufacturer can cover a less valuable metal with the luster and beauty of a luxury metals at a fraction of the cost. For example, electroplating thin layers of chrome on kitchen appliances provides a pleasant, shiny appearance.
What is galvanization? Galvanizing is an old process, having been used since the mid-1700s. It involves applying a zinc coating to steel or iron, mainly to prevent rusting and corrosion. The most common galvanization method involves dipping the metal part into a pool of molten zinc.
Benefits of galvanizing:
It's simple and more affordable compared with other metal finishing techniques. So if your product’s market is not high-end, you may be able to get away with galvanizing.
Galvanized metal has found its way into several household appliances, including washing machines and air conditioner housings. The nice thing about galvanized steel is that it’s low-maintenance -- your customers won’t have to repair or replace it often, as it has self-healing properties.
About 15% of all metal component finishing is done via powder coating.
Benefits of powder coating:
It's a combination of aesthetics and function. Many product makers love the powder coating process for its high-quality, high-end look. And despite what you might’ve heard, it comes in a huge variety of colors, textures, and patterns. It also applies a thicker, more even coat than paint, mitigating the need for additional coats. If your component or product will be customer-facing and dependent on a great look, powder coating’s your choice.
Powder coating also offers modest improvements to product durability, a bit more so than paint. It’s also more affordable than many other finishing processes -- did you know that any excess powder can be collected and reused?
What is paint? We’re guessing you already know the answer. Specifically, wet industrial painting involves the use of a spray, pump, or vessel to distribute paint evenly.
Benefits of paint:
The main, obvious benefit to painting metal is appearance. Paint comes in a seemingly endless number of shades that are easier to achieve than with powder coating. (Customized colors for powder coating sometimes adds cost.) And if you actually want a thinner coat, you’re better off with paint than powder.
Paint is affordable to purchase and easy to apply. If you’re on a tight budget and not concerned about long-term wear and tear, paint may work for you. Just remember that paint doesn't offer the same structural and durability benefits as some of the other finishing techniques on this list.
What is stainless steel? This high-end steel contains chromium for resistance to rust and tarnishing.
Benefits of stainless steel:
There's a reason why stainless steel has become the material of choice in several industries. It has a uniquely sleek look, even if you don’t apply an extra finish. Of course, there are several stainless steel surface finishes available, such as polished.
A stainless steel surface is smooth, reflective, and clean-looking. Stainless steel is also rust- and corrosion-resistant.
Where would this be potentially useful? The medical and food industries, for starters. A mirrorlike, rust-free finish gives a perception of cleanliness. This is incredibly important in food preparation or hospital settings. Stainless steel is easy to clean and sterilize.
A drawback of stainless steel is that it's expensive, but it’s still cheaper than gold, copper, or silver.
What is e-coating? Short for electrophoretic painting or electrocoating, e-coating is what you’d get if painting and plating had a baby. E-coating starts with your component being dunked a water-based solution containing a paint emulsion. Next, voltage is applied, condensing the paint onto the part.
The result is a thin, protective layer. Color options are very limited, with the most common being black.
Benefits of e-coating:
This is a very uniform finish that provides 100% coverage, no matter the part’s shape. Because of the way it’s applied, e-coating is typically a better option than powder coating when finishing parts that contain hard-to-reach areas.
The coating is resistant to corrosion and wear, and it promotes adhesion. E- coating layers can be made thin, after which you can apply paint. (This is common in the auto industry.)
Note that you can combine powder coating with e-coating. This could prove beneficial in a variety of projects:
Frequently Asked Questions About Metal Finishing TechniquesThese are some of the most frequently asked questions about metal finishing techniques What factors should be considered when determining the ideal finishing technique for a new product design?Choosing the right metal finishing technique for a new product design involves a nuanced approach. Start by understanding the product’s specific needs, such as how it will perform under conditions like exposure to moisture, chemicals, or heavy wear. The finish should enhance the product’s functionality, whether by improving its durability or resistance to environmental factors. Equally important are the aesthetic requirements — color, texture, and overall look should match the product’s market positioning and user expectations. Budget constraints also play a role, as the costs of finishing techniques vary and impact both initial expenses and future maintenance. Additionally, ensure the selected finish aligns with the product’s material and adheres to relevant industry standards or regulations. How do industry standards or regulations influence the choice of metal finishing techniques?Industry standards and regulations can significantly influence the choice of metal finishing techniques by setting specific requirements for performance, safety, and environmental impact. For instance, certain industries, like aerospace or medical, have stringent standards for corrosion resistance and durability, which may dictate the use of particular finishing techniques. Regulations may also mandate compliance with environmental standards, such as limits on volatile organic compounds (VOCs) in coatings or requirements for waste management during the finishing process. Adhering to these standards ensures the finished product meets safety and quality benchmarks while minimizing its environmental footprint. What are the potential environmental impacts of each metal finishing technique, and how can these be mitigated?Each metal finishing technique has potential environmental impacts. For example, processes like electroplating and e-coating often use chemicals that can be hazardous if not managed properly. Powder coating and paint applications can release VOCs, which contribute to air pollution. To mitigate these impacts, manufacturers can adopt best practices such as using less toxic chemicals, implementing efficient waste management systems, and ensuring proper ventilation and containment measures. Advancements in technology, such as the development of eco-friendly coatings and recycling systems for excess powder, can further reduce environmental impact. Ensuring compliance with environmental regulations and investing in sustainable practices also helps minimize the ecological footprint of metal finishing processes. |
Choosing the right metal finishing technique can make a big difference in how your product performs and looks. Each method has its own benefits, whether boosting durability, preventing corrosion, or achieving the right appearance.
By understanding what’s most important for your product and budget, you can pick the finish that works best for you. A well-chosen finish can improve the function and appeal of your product, setting it up for success.
Avoid the hassle of deciding on your industrial metal finish — trust an experienced manufacturer to handle it for you. A manufacturer with expertise in various finishing services has the knowledge to guide you based on what has proven effective.
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This article was originally written in October 2019 and was recently updated to reflect industry trends