Top 12 Metal Surface Finishing Types You Must Know

When working with metal, there are a large number of procedures that must be applied. One of the most important is the final surface finishing given to the various metal parts.

There are many processes that can change the metal surface coating, but many people don’t know the difference, function, and confused about which type is suitable for their metal projects. So, I write this guide to show you the commonly 12 types of metal surface finishing.

Let’s begin. (The ranking is random, not from the popular used to unpopular)

Table of Contents
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    1. Anodizing

    anodizing

    What is Anodizing?

    Here we should mention that anodization is an electrolytic process of passivation. In particular, this is applied to different metal parts, exactly on the surface. By doing this it is possible to add a natural layer of greater thickness. When working with this metal obtains greater durability and resistance.

    Advantages of Anodizing

    In particular, it is an extra layer that makes the metal much more resistant than a layer of paint. So this allows for greater durability in general.

    So, this layer becomes part of the base metal directly. At the same time, the metal can be properly visualized, as it is a translucent layer.

    As we have mentioned, anodizing can provide a longer life for the metal and the same extra layer. Besides, sunlight cannot affect this new layer either.

    Disdvantages of Anodizing

    The main disadvantage here is that this is an expensive procedure. This means that large productions of anodized parts must be made. This is why we can get anodized aluminum in massive products such as electronic devices.

    Applicable Materials of Anodizing

    In principle, the most common application of anodizing is aluminum. Since it is a light metal, we can find anodized aluminum in a large number of electronic devices.

    So, a second application is made of titanium. It is used a similar procedure to provide this metal with high resistance and durability.

    Available Colors of Anodizing

    First of all, it is important to consider that the anodizing layer applied to aluminum and titanium is translucent. Thus, by itself, this layer does not provide any particular color. Beyond that, it is possible to apply a large number of more colors.

    Frequently Used in These Industries

    Concerning anodized aluminum, many industries must this procedure the most. Among them are the automotive industry, aeronautics, and construction. Also, decoration and lighting, machinery, and industrial and electronic products.

    Cost of Anodizing

    $$$$$

    2. Physical Vapor Deposition (PVD)

    PVD Coating

    What is Physical Vapor Deposition (PVD)?

    Physical vapor deposition consists of a procedure that aims to convert a specific solid material into vapor. This is done using a set of procedures, such as spraying or heating. Once a specific vapor is obtained from a substance it is used in another object. In this way, it is possible to apply a coating or a thin film to a certain material.

    Advantages of PVD Coating

    It is a safe procedure to perform compared to other methodologies using chemicals that are harmful to the environment.

    Also, this procedure can provide greater resistance to a large number of inorganic materials.

    In comparison to other procedures, this method is one of the ones that provide you with greater durability and resistance to a certain material.

    As we have mentioned the level of versatility allows this procedure to apply to a large number of different options and materials.

    Disdvantages of PVD Coating

    One of the main disadvantages is the high cost of applying this procedure to any material. This happens because very complex machines and specialized workers are required.

    On the other hand, it is necessary to add that the work time required by this procedure is somewhat extensive. This is because the speed of operation is somewhat low.

    Another advantage is that it requires constant attention from specialized workers. In particular, this is because the temperatures are high, which also makes a constant cooling water system necessary.

    Applicable Materials of Physical Vapor Deposition (PVD)

    Several industrial coatings are the most widely used. Among them are aluminum nitride, chrome nitride, zirconium nitride, titanium nitride. It is applied to a large number of materials such as bronze, copper, aluminum, thin-film, watch parts, optical components, among others.

    Available Colors of Physical Vapor Deposition (PVD) Coating

    As well as color applications, they are also available in a wide range of options. In particular, the color available depends on the materials used in the vaporization process.

    Frequently Used in These Industries

    Among the industries that most use this method are the automotive industry, as well as heavy truck manufacturing. appliance industries, packaging containers, and various other applications.

    Cost of PVD Coating

    $$$$$

    3. Polishing

    Polishing

    What is Polishing?

    In this case, polishing is a procedure that aims to provide a shiny and satin surface to a particular type of metal. For this purpose, different industrial procedures are usually carried out. One of them is done with the use of a burnisher to perform a hardening by deformation. It is also possible to perform a mechanical or manual process through abrasion.

    Advantages of Polishing

    One of the best advantages is that an excellent level of brightness and surface leveling of the polished metal is obtained.

    In turn, there are different procedures that a person can choose to obtain the best result.

    That is why other evident advantages are the relatively accessible cost that is possible to obtain with some of these procedures.

    Disdvantages of Polishing

    A major advantage here is that adequate ventilation is required because the risk of contamination is high.

    When mechanical polishing is carried out, then the work is highly labor-intensive. In turn, the level of gloss obtained has a certain lifespan. So, the new gloss will become opaque within a certain period.

    On the other hand, a significant initial investment may be required when an electrochemical polishing is intended. Additionally, this procedure does not offer greater resistance and durability to the metal that is subjected to the procedure.

    Applicable Metal Materials of Polishing

    In particular, this procedure is often used on certain metals such as chrome, nickel, aluminum, copper, brass, stainless steel, silver, and gold. This same procedure can also be used on other metals with some degree of purity.

    Available Colors of Polishing

    In principle, no color is added through this procedure on a metal. Beyond that, the procedure of metal polishing seeks to awaken a greater brightness in the same color of the metal.

    Frequently Used in These Industries

    Here we can mention that the main applications are in dentistry, woodwork, casting, ironwork, watchmaking, goldsmithing, jewelry, and jewelry. In particular, the main application here is to obtain a higher quality finish on a given metal.

    Cost of Polishing

    $$$$$

    4. Electroplating

    Electroplating

    What is Electroplating?

    In short, it is an electrochemical treatment that aims to add layers to a certain metal. For this purpose, an aqueous solution, the metal cations, are incorporated.

    After these components are sedimented, a layer can be created that provides different advantages. Besides, it is possible to obtain a thickness of different levels according to a large number of factors.

    Advantages of Electroplating

    An industry that is dedicated to this procedure can operate 7 days a week and 24 hours a day.

    Here too, both water use and waste generated during production can be reduced. This in turn allows for greater control over the entire process compared to other processes.

    Therefore, it is an environmentally friendly method that does not produce too much pollution.

    Finally, another advantage we can add is that the metal coated with a new layer will get a better finish and an increase in the level of resistance. This is why it is a versatile procedure compared to other methods.

    Disdvantages of Electroplating

    One of the disadvantages is that a somewhat long production time is required depending on the galvanizing process.

    Also, when it comes to electroplating brushes, more involvement of the skilled worker is required. At the same time, it is not possible here to obtain a very thick coating.

    Applicable Metal Materials of Electroplating

    It should be mentioned here that this procedure is used on a large number of metallic and non-metallic materials. Therefore, one of the most common materials in which this procedure is applied is nickel. On a metal surface finishes chart, this method should not be missed.

    Available Colors of Electroplating

    In particular, the specific color depends largely on the materials used for the electroplating process. Thus, some common colors are the color of chrome, gold, and silver.

    Frequently Used in These Industries

    Generally, we can find some products like electronic jewelry cards and watches that have an additional layer by electroplating. Thus, additional resistance can be obtained in any of these products. However, the important thing here is that the aim is to obtain a more pleasant finish in general.

    Cost of Electroplating

    $$$$$

    5. Electrophoretic Coating

    Electrophoretic Coating

    What is Electrophoretic Coating?

    This is a procedure that requires paint and demineralized water that is prepared in a vat. After that, a certain set of pieces must be submerged to apply a certain electric current. Once this happens, the chemical reaction that results from this process allows the paint to adhere to the surface of the different metals that have been submerged.

    Advantages of Electrophoretic Coating

    In principle, a layer is obtained that offers a very useful thickness. Even this additional layer has no porosity whatsoever and is very uniform.

    The procedure can be applied very simply to certain relatively complex objects. Besides, the speed of production means that the working time is not very long.

    This is why the procedure can be applied to a large number of metals, as well as other non-metallic materials. Compared to other painting procedures and technologies, this method is very environmentally friendly.

    Here, water is mainly used, which reduces costs and avoids some problems. In particular, flammability will not be a problem here. That is why this metal surface finishing is a low cost.

    Moreover, the excellent variety of colors is combined with a high level of paint adhesion. It is also very useful to be able to resist corrosion in the most efficient way.

    Finally, it is possible to efficiently use the different materials required for this procedure. This is why the costs related to the production process are not very high.

    Disdvantages of Electrophoretic Coating

    Specialized machines and equipment are required to carry out this procedure. Also, relatively specialized workers are required to use these machines.

    Applicable Metal Materials of Electrophoretic Coating

    Materials used may include metals, ceramics, dyes, pigments, and polymers.

    Available Colors of Electrophoretic Coating

    In particular, this type of method can provide a wide range of colors that are available to choose from. This allows for an excellent level of versatility when making an application.

    Frequently Used in These Industries

    This process is usually carried out on a large number of metal products. This is why we can find fasteners, beverage containers, metal furniture, home appliances, electronic switching equipment, heavy equipment, tractors, automobiles, and vehicle parts.

    Cost of Electrophoretic Coating

    $$$$$

    6. Brushed Metal

    Brushed Metal

    What is Brushed Metal?

    Through this procedure, the 120-180 grit wheel or a band is used to perform the polishing. A unidirectional satin finish is then applied to a specific metal.

    From there, it is necessary to use a medium non-woven abrasive pad, a band, or a greaseless compound with 80 to 120 grit. This allows a metal part or object to be obtained with a much more uniform and pleasant appearance.

    Advantages of Brushed Metal

    No large budget is required to implement this procedure. Beyond that, large parts may require more specialized machines.

    Here it is possible to obtain a surface with a more pleasing appearance to the eye. This is why metal polishing is often applied to certain small objects such as household appliances.

    Disdvantages of Brushed Metal

    Here the corrosion resistance of different factors is usually reduced because of this method. This can also lead to some oxidation on the surface in a simpler way.

    In connection with this, it should be mentioned that the brushing finish on a metal increases the possibility of damage. This is why it is used as a decoration procedure.

    Applicable Materials of Brushed Metal

    In particular, this procedure is applied to some metals such as nickel, aluminum, and stainless steel. There may also be other metals that require polishing, although this is not the norm. This allows us to obtain a shiny and pleasant appearance.

    Available Colors of Brushed Metal

    As with other methods, metal polishing does not apply any special color. Here the metal that goes through this procedure simply gets a higher gloss. So the original color of nickel, stainless steel, or aluminum is still maintained. To incorporate a different color, other methods or procedures must be used.

    Frequently Used in These Industries

    On the one hand, it is possible to find a brushed finish on certain small products, such as household appliances. The final design of automobiles as well as some architectural pieces must also apply this method.

    In turn, each of these areas applies a certain surface roughness. On the other hand, it is also possible to find watches and jewelry in which a metal polishing has been applied.

    Cost of Brushed Metal

    $$$$$

    7. Photochemical Etching

    What is Photochemical Etching?

    In this case, we are talking about a procedure that is carried out to manufacture components through a chemical milling process. In this way, engravers and photoresistors are used to engrave certain selected parts. In this way, it is possible to choose different subtypes of photochemical engraving. Extremely precise parts can be obtained here.

    Advantages of Photochemical Etching

    Here the work time required to apply this procedure is not very extensive. That is why an excellent working speed can be obtained with the vast majority of the parts. Generally, it takes between 1 and 3 weeks to obtain an accurate result.

    Besides, a large number of expensive tools are not required. This reduces the total costs of the application of this procedure.

    In the same way, it is possible to realize good mass production and at the same time produce complex parts. For this purpose, the software is now being developed to facilitate both the design and manufacture of parts.

    Disdvantages of Photochemical Etching

    In this case, it is necessary to update the re-recording when a certain quantity of products has finished the procedure. This adds some additional work time.

    In turn, this procedure uses certain chemical components that must be specifically removed. In particular, when this is not done, then the environment can become considerably contaminated.

    Applicable Metal Materials of Photochemical Etching

    Here we can mention that a large number of alloys can be used to apply this procedure. So among the most common metals are aluminum, copper, and steel. These options are the most used because they are applied to a large number of industries.

    Some examples of them are metal gaskets, transformers and motor laminations, semiconductor conductor frames, heat sinks, pressure membranes, springs, microwaves, sensors, fuel cells, and others.

    Available Colors of Photochemical Etching

    In particular, the colors depend on each of the pieces selected for work. So no additional colors are usually added during this procedure.

    Frequently Used in These Industries

    As we mentioned this procedure applies to a lot of industries. First of all, the most common application is in the electronics industry. In particular, here the aim is to improve the surface finish by eliminating imperfections and irregularities.

    Other common applications are in aeronautics and micro electromechanics. Although here it is necessary to take into account some disadvantages in the procedure, it is a very useful method.

    Here you can work with aluminum up to 12 millimeters and titanium up to 5 millimeters thick. At the same time, the precision is not very high. Beyond that, it is still a useful procedure.

    Cost of Photochemical Etching

    $$$$$

    8. Powder Coating

    Powder Coating

    What is Powder Coating?

    A dry powder is used for this procedure as a type of coating on certain metals. Here the sense of this method is to provide a finish with a higher level of resistance. Therefore, this procedure is chosen instead of conventional painting. Therefore, through certain procedures, this coating is applied to different objects of today.

    Advantages of Powder Coating

    One of the main reasons for choosing this procedure is that it is a more durable layer. Also, the level of resistance to decoration, scratches, and chipping is higher. This is why this procedure is chosen for the most important appliances.

    On the other hand, it is a method that is more environmentally friendly. So it’s another excellent way to get a good finish without major damage.

    Finally, although it is a high initial cost, it is possible to save money in the long run. In particular, waste can be reduced here, and therefore production costs are lowered.

    Disdvantages of Powder Coating

    One of the main disadvantages is that it is hardly possible to apply this procedure and obtain very thin layers of coating. So, this increases the obstacles in production when it is intended to do so.

    Moreover, this process is not very efficient in resisting UV exposure. So, when this happens, the powder coating layer deteriorates and decomposes.

    Besides, retouching or changing the color of an already finished layer is a difficult procedure. Therefore, it is not advisable to make any changes to the finished layers.

    Applicable Metal Materials of Powder Coating

    Here the main metal in which this procedure is applied is aluminum. In particular, you need to take into account that if you use aluminum in bicycle or motorcycle parts, cars, drum fittings, aluminum extrusions, and of course a lot of household appliances.

    In the same way, there are also a lot of non-metallic objects where this powder coating can be applied.

    Available Colors of Powder Coating

    Here it is possible to choose a large number of colors in the final procedure. In particular, this is done by mixing different colors. So that the desired effect can then be achieved on different pieces of metal.

    This is why we can see bikes with a large number of colors. In turn, this procedure allows a layer of color much more resistant than other options.

    Frequently Used in These Industries

    In particular, companies that manufacture automotive appliances and other products apply this procedure. Both buildings and architecture also use this method for certain specific parts. Examples include signs, posts, fences, railings, window parts, and doors.

    On the other hand, other products such as ski bikes, bicycles, ski poles, golf clubs, and golf cards also apply this procedure. Additionally, factories of electrical elements, lighting fixtures, and antennas also take advantage of the advantages of powder coating.

    Cost of Powder Coating

    $$$$$

    9. Bead Blasting

    Bead Blasting

    What is Bead Blasting?

    In simple words, it is a procedure that seeks to remove certain components or impurities from a certain surface. To do this, fine glass beads are used and a high level of pressure is applied. In turn, it is possible to remove fungi and other components on metallic and non-metallic surfaces. This is a subtype of abrasive cleaning.

    Advantages of Bead Blasting

    One of the best advantages is that this component removal procedure can be applied to different materials. This is why this procedure is often applied in a variety of industries.

    Another advantage we can mention is that the result obtained can provide a much cleaner and more useful surface for subsequent production processes.

    Disdvantages of Bead Blasting

    Relatively complex initial equipment is required. This can considerably increase the initial cost required for these machines.

    On the other hand, the working time required can be somewhat extensive. Here it depends on the specific material to be worked with.

    Applicable Metal Materials of Bead Blasting

    Among the main metals in which this procedure is applied are stainless steel, aluminum, and mild steel. This is why it is a useful method for a large number of body parts, machinery components, and other non-metal materials.

    Available Colors of Bead Blasting

    Again, this procedure is not intended to apply any particular color. On the contrary, here it is simply necessary to clean the surface of a certain material. So the only important color will be that of the surface of the metal or non-metal material.

    Frequently Used in These Industries

    In particular, this procedure is often used to remove paint from certain vehicle parts. Therefore, it is usually used in the automobile and vehicle industry in general. The use of this method can also be found in other heavy industries, such as the manufacture of machinery.

    Cost of Bead Blasting

    $$$$$

    10. Plasma Electrolytic Oxidation (PEO)

    Plasma Electrolytic Oxidation

    What is Plasma Electrolytic Oxidation?

    In particular, this is a process that aims to transform a certain surface into a layer of ceramic oxide. This is used to obtain a surface with a higher level of density, durability, and resistance. For this purpose, a plasma-discharge is applied to the metal electrolyte interface.

    Advantages of Plasma Electrolytic Oxidation

    Here you get metal with a higher resistance to wear and corrosion. So, this allows us to increase the life span of any type of object or product on the market.

    In the same way, both electrical insulation and heat do not damage the structure of the metal that has this procedure.

    Disdvantages of Plasma Electrolytic Oxidation

    One of the main disadvantages is the high initial cost required for this method. Special materials and components are used during the procedure.

    On the other hand, it is necessary to mention that the production time can be longer concerning other methods.

    Applicable Metal Materials of Plasma Electrolytic Oxidation

    This procedure is usually used on certain metals such as titanium, magnesium, and aluminum. Due to the advantages obtained, then this application is found in a large number of industries.

    Available Colors of Plasma Electrolytic Oxidation

    In applying this procedure, no particular color is intended to be incorporated. Here the main objective is to obtain a surface with a higher level of resistance and durability. Beyond that, it is possible to apply some kind of coloring using other processes.

    Frequently Used in These Industries

    In particular, we can find the application of this procedure in the oil and gas industry, in the automobile industry, and aerospace. In particular, this method is required for the manufacture of pumps, pistons, wheel doors, engine covers, transmission shafts, landing gear, among others.

    Cost of Plasma Electrolytic Oxidation

    $$$$$

    Resources

    Learn more info about Plasma Electrolytic Oxidation

    11. Black Oxided

    Black Oxide

    What is Black Oxided?

    Here this procedure seeks to generate black oxide to provide greater protection to a particular metal. Even the black or blue shade depends exclusively on the procedure performed. For this purpose, an electrochemical conversion coating is performed.

    Advantages of Black Oxide

    One of the main advantages is that a certain level of protection is obtained. Therefore, it is possible to reduce the risk of corrosion of the metal.

    In turn, the durability of the surface can provide a higher level of resistance.

    Disdvantages of Black Oxide

    One of the advantages is that this procedure can only be used on ferrous materials. In particular, polymer and aluminum parts are not an option for applying this method.

    When hot-bluing an aluminum part, the consequences can be severe. The user may suffer from certain severe chemical burns.

    Applicable Metal Materials of Black Oxide

    In particular, these procedures are used on stainless steel, cast iron, or steel parts. Different procedures are used depending on the results to be obtained. Also, it is one of the steel finished types that provides excellent advantages.

    Available Colors of Black Oxide

    Here the only two colors available are blue and black oxide. Either of these two colors are dark and are obtained from the procedure itself.

    Frequently Used in These Industries

    In particular, the most common use of this procedure can be found in the arms industry. This method is usually required in the manufacture of shotguns and other weapons.

    Cost of Black Oxide

    $$$$$

    12. Spray Painting

    Spray Painting

    What is Spray Painting?

    Here we can mention one of the most common processes in the application of paint on a piece of metal. When using a manual or automatic spray gun, paint is applied through the air. This requires certain implements that are key to the application of varnish, ink, or paint.

    Advantages of Spray Painting

    Here the procedure is very simple to apply for any type of user. Good results are obtained without the need for specific technical knowledge.

    Additionally, the required working time is not very extensive. When you have the right equipment, you can do a good job at a good speed.

    Disdvantages of Spray Painting

    One disadvantage to consider is the pollution that is produced in the environment. Since it is a method that is applied through the air, then it is easy to pollute the environment. Also, special safety equipment of great importance to the user is required.

    In the same way, the smell generated by spray paint is very strong. So this can be an obstacle for some users.

    Applicable Metal Materials of Spray Painting

    Among the metals that can be spray-painted are stainless steel, aluminum, titanium, copper, and a host of other options. It is even possible to apply this procedure to other non-ferrous materials such as wood, plastic, and other options.

    Available Colors of Spray Painting

    Among the available colors, we can mention a lot of different options. This is especially the case since the main objective is to obtain a particular design, look, and color.

    Frequently Used in These Industries

    Among the most common uses, this procedure is applied in the marine, decorative, and automotive industries. It can also be used in the cosmetic industry, scenic painting, furniture finishing, and architectural coating. It’s one of the most popular types of metal surface finishing.

    Cost of Spray Painting

    $$$$$

    How to Choose?

    Choosing the best possible method can be a bit overwhelming for a novice user. That is why the following tips may help in the final choice.

    According to Function

    An important aspect that you should analyze is the specific benefits that you want to obtain on a metal. Some of the options we have listed can provide you with resistance to corrosion and oxidation.

    So, in the same way, it is also possible to obtain a much more resistant and durable surface in general. Here then it is possible to obtain a part that resists more conveniently to the wear and tear of time.

    On the other hand, some procedures seek to obtain a more pleasant and uniform surface. So, here the important thing will not be the resistance or durability. On the contrary, this type of finish can provide a better appearance and decoration.

    According to Color Requirements

    As mentioned above, not all metal surface finishing can provide the same colors. Therefore, in that case, it will be necessary to choose the most appropriate method to do so. In particular, some processes, such as spray painting, offer the possibility of choosing the most appropriate color.

    Even this can be important for certain objects. Some of these are household appliances or decorative pieces in general. Additionally, the anodizing process can provide the possibility of obtaining colors along with other benefits. Therefore, it can be useful to combine a good level of resistance with a particular aspect.

    According to the Material

    Another important consideration is the material to be worked on. Therefore, not all procedures are useful for any type of metal. Generally, aluminum, stainless steel, or steel are useful for the vast majority of processes. When you want to work with copper or a titanium alloy, then you will need the right procedure.

    According to the Budget

    Last but not least, the necessary budget is also another aspect to consider. Some of the procedures we have listed require a high initial cost. Beyond that, the cost of production can be reduced with the right technique.

    Summary

    After selecting the most efficient type of finish for you, you can start noticing the results. In turn, this metal surface finishing guide will help you avoid mistakes from the start. In this way, you will be able to reduce the initial costs and become an expert, depending on what you want to do.

    If this guide is helpful to you, please share with more people, thanks very much!

    If you have metal parts needs in plan, please feel free to contact us. DEK is your best manufacturing parter, which good at CNC machining, Metal 3D printing, Die casting, Sheet metal fabrication. Contact Us Today!

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