Common Surface finishes

Surface treatment of parts? Now consult us.

  • You can choose more than thirty ways.
  • Professionals have more than 10 years of processing experience.
  • Provide processing effect photos in the fastest three days.


  • A good product is not just machined, various surface finishes shall be applied to ensure the corrosion resistance, wear resistance, aesthetic and longer service life.
  • GREFEE has years of prototyping experience, CNC, 3D Printing, etc. We provide a series of one-stop services ranges from machining, surface treatment as well as assembly.
  • Therefore, in addition to CNC technology we are also experienced in surface treatment including painting, baking, powder coating, sand blasting, shot blasting, anodizing, hard anodizing, micro arc oxidation, electroplating, electrophoresis, laser engraving, silk screen, brushing, mirror polishing, dyeing, black oxide, CD pattern, etching, high glossing, etching pattern, glue dropping, etc. The products will be like icing on the cake with a good finish.


Anodizing is an electrolytic process which converts the surface of metal parts into a protective film.

The natural oxide layer increases resistance to corrosion and wear, and provides better adhesion for paint primers and glues than bare metal does. With anodizing finishing you can get a product with a longer service life and more color options. There are different types of anodizing that can be divided into: ordinary anodic oxidation, brushing oxidation, hard oxidation, thick film oxidation, micro arc oxidation, etc. Materials that can be oxidized are aluminum alloy, magnesium alloy, titanium alloy and so on.


Basically, the electroplating refers to immersing the parts in the metal salt solution as the cathode whereas the metal plate works as anode, to generate a metal coating on a solid substrate to achieve the reductions of cations of that metal by the direct electric current. Electroplating can benefit your products in many ways. it can make your products more aesthetically pleasing and brings more market potential. There are many different types of electroplating so far, which have been widely applied into different products manufacturing.


Electrophoresis (EP) is the short name of electrophoretic phenomenon, which refers to the phenomenon that charged particles move towards to the opposite electrode under the action of electric field. The separation technology of using different moving speeds of charged particles in the electric field is called electrophoresis technology. As its industrial demands increasing, electrophoresis treatment has been a popular method for keeping metal luster no matter colors you’ve selected and improving corrosion resistance of the products surface. Electrophoresis treatment has little effect on the accuracy of products. The electrophoresis film thickness in one side is about 10-25um. Actually the thickness can also be customized if you prefer a thicker film.


Passivation is also known as chromate treatment which is a kind of acid pickling technology. the passivation process uses acid or ultrasonic cleaning to remove free oil scale, rust stain and oxide on the surface. After that a protective outer layer of shield material will be created by the chemical reaction of passivation solution. This oxide layer that is less likely to chemically react with air and cause corrosion which helps to prevent corrosion and resists rust. The color of passivation films altering depends on the material types. Passivation won’t affect the tolerance of the product as it doesn’t has an impact on the thickness of the product.

Black Oxide(Blackening)

Blackening, also known as bluing, which is a process used for improving the corrosion resistance by generating an integral protective oxide film on the metal surface. Products are soaked in intense oxidizing chemical solution to cut off the air contact to stop the occurrence of rust.   This technique is applicable to ferrous materials like iron and steel.


QPQ is the abbreviation of Quench Polish Quench,it is sometimes known by the brand name of Tufftride, Tenifer or Melonite. The process is to put ferrous metal parts into two different kinds of salt solutions, during which multiple elements been penetrated into the metal surface and forms a composite infiltration layer, so as to achieve the purpose of improved cosmetic surface. QPQ finish helps to have good coefficient of friction, fatigue resistance, corrosion resistance and small deformation. QPQ process is suitable for all kinds of iron and steel materials.

(Note: Black Oxide is not work for stainless steel products, QPQ can help SS products get a black surface)

Laser Engraving

Radium carving is commonly applied to engrave logo or pattern on products through optical principles, is also named Laser engraving or loser marking.Radium carving effect is permanent and has high surface quality. It is suitable for all kinds of metal and plastic products.



Polishing is a kind of surface finishing process for smoothing a workpiece’s surface, which leads to a brighter and aesthetic surface. Thus, transparent polishing shall be a good choice for you if you are looking for a beautiful surface. Metal polishing has two types: mechanical polishing and electrolytic polishing. Electropolishing can be used to replace heavy mechanical polishing, especially for parts with complex structure and parts that are difficult to be polished by hand or mechanical methods. Electropolishing is often applied for steel, aluminum, copper and other metal parts.

Silk screen printing

Screen printing transfers ink pattern onto a substrate surface by a ink pattern onto a substrate surface.

Normally, it is single color printing mode each time. However, It can apply several screens as it can produce a multi-colored image or design as you wish GREFEE has many successful projects that to print 6 colors on one product surface (including black, red, blue, yellow, white and green). If you prefer to have a more lasting screen printing, the UV layer could be added after the screen printing to prolong its service life. The screen printing is suitable for all kinds of metal and plastic materials, and can also be applied together with surface treatments such as oxidation, painting, powder spraying, electroplating, electrophoresis and so on.

Brushing finish

Brushing is a type of surface treatment that forms lines on the surface of the metal products through flat pressing abrasive belt and non-woven roller brush which provide a durable, high-traction surface. A good brush finish is something of an art.

Brushing finish is becoming more and more popular in modern life. It is widely used in smart phones, computers, displays, furniture, electrical appliances and so on.

Powder Coating and Painting

Powder coating and painting are two normal surface finishes in metal parts. It’s also been commonly applied in precision parts and small batch customized products.  It is usually used to form a hard finish that is tougher than conventional paint which can protect the surface from corrosion and rust, and can also provide a beautiful surface. In GREFEE you can choose different textures (fine grain, coarse grain, leather grain, etc.), different colors as well as different glossiness (matte, flat, high gloss).


Sand blasting is an effective method for surface treatment of metal products. As the sand particles strike the surface, it creates a smoother and more even texture which can improve the cleanliness and roughness of the products. The adherence and durability will also be improved at the same time between products and coatings. It has been the choice of pretreatment in many surface treatments, for instance, sand blasting + oxidation, sand blasting + electroplating, sand blasting + electrophoresis, sand blasting + powder spraying, sand blasting + paint baking, sand blasting + passivation, etc.

Teflon Coating

Also known as Teflon spraying, it is a very special surface treatment. It has the characteristics of superior viscosity resistance, non-viscosity, high temperature resistance, low friction, high hardness, non-humidity and high chemical resistance, etc. Therefore, it is widely used in food industry, tableware, kitchenware, paper industry, medical devices, electronic products, automotive parts, chemical equipment and so on. In the meanwhile, Teflon coating can protect the material from chemical corrosion, which lengthens the useful lifespan of the parts.

In addition to the above surface finishes, GREFEE also provides shot blasting, dyeing, CD pattern, etching, high glossy, etching pattern, glue dropping, etc. for more details, please feel free to contact us.


Electroplating coat thickness chart

CategoryElectroplating TypeThicknessFeatures
Barrel platingNickel8um/minGlossy and good corrosion resistant
Barrel platingNickel8um/minSmooth and average anti-corrosion
Barrel platingNickel8um/minSmooth and good corrosion resistant
Barrel platingBlue zinc6um/minGood corrosion resistant, soft blue
Barrel platingColor zinc8um/minAverage corrosion resistant,colorful
Barrel platingGreen zinc6um/minGood corrosion resistant, army green
Barrel platingWhite zinc4um/minPoor corrosion resistant, zinc white
Barrel platingBlack zinc6um/minGood corrosion resistant, pure black
Hanging platingSteel chrome platingNi 8um/minCass experiment, continuous spray for 16 hours, 7 level.
Hanging platingSteel chrome platingCr 0.2~0.3um/minCass experiment, continuous spray for 16 hours, 7 level.
Hanging platingZinc alloy chrome platingCu 10~25um/minNeutral salt spray test for more than 96 hours
Hanging platingZinc alloy chrome platingNi 5~10um/minNeutral salt spray test for more than 96 hours
Hanging platingZinc alloy chrome platingCr 0.2~0.3um/minNeutral salt spray test for more than 96 hours
Hanging platingCopper chrome platingCu 10~25um/minNeutral salt spray test for more than 96 hours
Hanging platingCopper chrome platingNi 5~10um/minNeutral salt spray test for more than 96 hours
Hanging platingCopper chrome platingCr 0.2~0.3um/minNeutral salt spray test for more than 96 hours

Any other questions?

The powder coating does not contain any pollutant ingredients, which is environmentally friendly and pollution-free, while paint spray contains. The powder for powder coating has a high-usage rate up to 95%. However the paint can only be stored for a short time. There are more options of paints, thus relatively less categories of powders. Powder coating has a thicker film than the paint spraying, on the contrary the spray paint has a smoother surface.
laser engraving process forms logo and pattern on the product surface through laser beam, and can also remove any coats on the products surface. The patterns are concave; While Silk screen printing treatment transfer logos and patterns onto the products substrate through ink adhesion, which is convex. Laser engraving makes the logo and pattern that has the same color with the raw material, while the logo and pattern color of silk screen printing process can be customized as the ink is optional. In terms of wear resistance, laser carving is better than silk screen printing. Different cost. Laser carving process is more economical because it does not need film as silk screen printing does.
Steel can be blackened, while stainless steel can’t, only QPQ process can help to achieve a black surface.
Sandblasting grades according to the fine degree.0.8 um、1.6 um、3.2 um、6.3 um、12.5 um、25um.
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