Let’s Discuss Different Types of Surface Treatment Process

Jack Lie CNC machining expert

Specialize in CNC Milling, CNC Turning, 3D Printing, Urethane Casting, and Sheet Metal Fabrication Services.


You might not be aware of the surface treatment process that we will relate to in this article. So, here are 21 surface treatment processes:

1. Micro Arc Oxidation

Micro arc oxidation is well known as micro-plasma oxidation that involves electrical parameters and electrolytes to complete the process. With the help of arc discharge, a ceramic film of base metal oxide is grown using instantaneous high-pressure and high-temperature on the surface of aluminum, magnesium, titanium, and their alloys.

2. Metal Wire Drawing

Metal wire drawing is typically used to form decorative lines on the surface of the material. Primarily, the workpiece is intended to get used as a decoration piece.

3. Bluing

Bluing is a process of filling the whole carcass using the color glaze and then burn it in the blast furnace under the temperature of 800 degrees. Usually, the color glaze is obtained after melting the sandy granular in liquid form, and then it is used in the carcass for filling. In the initial steps, the color glaze is lower than the wires used in making the carcass, and later, the color glaze gets done repeatedly to bring it to the same level as wires.

4. Shot Blasting

It is a cold working process that proceeds with the bombardment of pellets on the surface of the workpiece to enhance the fatigue strength of metal using the implant residual compressive stress.

5. Sand Blasting

Sandblasting includes the process of roughing the surface of the material using high-speed sand. Different abrasive materials in combination with sand get blasted on the surface of the metal with very high velocity. Meanwhile, the varieties include quartz sand, copper ore sand, Hainan sand, and iron sand. After exposure to the sand, the surface of the material becomes quite adorable.

6. Etching

Etching is when an excessive part of the material gets removed by utilizing a chemical reaction or physical impact. To broader overview this term, it is also necessary to cover the word ‘Photochemical,’ which is alternatively used for the etching.

Typically, the photochemical advances remove the protective layer from the material’s surface, which will be etched. This move ensures etching will result in the form of an even surface instead of pits and uneven patterns on its surface. In short, the photochemical process gets streamlined to achieve the effect of corroding and dissolving.

7. In-Mold Decoration

In-Mold Decoration (IMD) is also known as painting-free technology. By now, the IMD has emerged as one of the most popular techniques as a surface decoration technology. Mainly, there are three parts of the process:

 Surface hardening transparent film for making the surface impregnable against scratches and etches.
 Middle printed pattern layer intended to add design on the surface of the workpiece, and
 Injection layer stuck on the back to preserve the original color and shine of the print on the surface of the workpiece.

8. Out-Mold Decoration

Out mold-decoration (OMD) is a tactile, visual, and functional integration display. This technology has been brought by IMD and incorporates 3D surface decoration technology, metallization characteristics, and texture structure.

9. Laser Carving

Laser craving, also known as laser making or laser engraving, is a surface treatment process utilizing optical principles. The method comprises the use of laser beams used to print on the surface of the metal or inside the transparent material.

10. EDM

EDM stands for electrical discharge machining. It is the process of removing conductive materials with the help of electro-etching. Technically, the process gets done during the pulse discharge between two electrodes immersed in working fluid.

The tool electrodes are commonly used in corrosion-resistant electrical material with high-melting-point, easy processing, and good conductivity during the process. The glaring examples of such tool electrodes are copper-tungsten alloy and molybdenum.

In EDM, during the process, the tool electrodes become worn. However, the consumption of electrodes is still lower than the amount of material removed from the metal’s surface.

11. Laser Texturing

Laser texturing uses a high-energy and high-density laser to react with a steel surface to form the desired pattern on its surface. Most commonly, laser texturing gets used for etching, pear field, and drawing snakeskin or other decorative lines on the material’s surface.

12. Pad Printing

In pad printing, there is a curved pad made up of silicon gravure and silicon rubber material. The ink is dipped on the gravure to the pad’s surface. After that, this pad gets pressed on the object where it is needed to print.

13. Screen Printing

Screen printing is used to make screen printing plates. These plates get made up of hand-painted film or photochemical plate-making methods. Meanwhile, screen printing is used to bind silk fabrics, synthetic fiber fabrics, or screen-to-screen frames of metals.

Presently, the photo engraving process is utilized to make the screen-printing plates using a photosensitive material. The ink is moved to the material through the mesh of the graphic part, which squeezes the blade to print the same graphics as the original ones are.

14. Direct Thermal Printing

Direct thermal printing is applying the heat-sensitive agent to the paper to convert it into heat-sensitive recording paper. By now, the use of direct thermal printing has expanded a lot since it offers the best printing that lasts longer. Typically, the thermal recording paper alters the chemical and physical properties of the material, which is under the action of heat to get the surface printed.

15. Heat Transfer Printing

The heat transfer paper follows the conventional printing process but on a special transfer paper with a special ink. The paper is passed through the printing process (printers) to print that paper. But the process is followed by one more printing phase, which is carried out using a specific transfer machine. This unique transfer machine helps print the exact shape as the original graphic is, and the process undergoes a high temperature and a high pressure.

16. Planography

Planography uses the principle of oil-water separation, which is usually absent in any other printing process. In planography, graphic and non-graphic parts are on the same plane to distinguish between the pattern and non-pattern parts of the printing screens. In the first step, the water is supplied to the non-graphic printing plate and protects it so that the non-graphic printing plate is fully immersed and wet with water and secure against its exposure to ink.

The link is provided to the printing component to the printing plate from the ink supply device. As the non-graphic printing plate is immersed in water and protected against its exposure to ink, the ink can only be provided to the printing plate’s graphic portion. Afterward, as the last step, the ink present on the printing plate is transferred to the milk skin. Then the pressure between the impression cylinder and rubber roller is utilized to transfer the ink on the milk skin to the material that needs to get printed. Thus, it can be said that planography is an indirect method of printing.

17. Curved Surface Printing

When it comes to curved surface printing, the gravure engraved is used with characters or patterns. The ink is placed in the gravure engraved, and then it is used to print the textures or designs onto the curved surface. Later, these patterns and characters are shifted on the surface of the molded product using the curved surface. In the last step, the ink is made to stay on the molded product using ultra-violet light irradiation or heat treatment.

18. Hot Stamping

Hot stamping is used to stamp the dual sides of any of the materials. The stamp is made up of a rigid material, most probably of metal, and utilizes liquefied ink to print the surface. The process starts when the substrate gets put under the stamp, and it prints patterns and characters on its surface. For durability and better cohesiveness of ink on the surface, the process is carried out under high temperature and high pressure.

19. Water Transfer Printing

Water transfer printing is a comparatively less old printing approach that operates using printing film. The printing film is placed in the water tub, and the substrate gets passed through that water. Furthermore, it uses high pressure to hydrolyze the printing film on the substrate.

20. Flat Screen Printing

In flat screen printing, the mold of the flat screen is made up of the nylon or polyester screen, which gets fixed on the square frame. The pattern part of the flower plate passes through the color paste, while the non-pattern part of the flower plate remains covered with the film layer of polymer. While the printing cycle is going on, the flower plate puts stress on the fabric, and the plate is filled with the printed color.

21. Calendaring

Calendaring gets used explicitly for the finishing of leather as its last process. The process uses the plasticity of fibers under diverse heat conditions to flatten the fabric’s surface to improve the gloss on the surface. After adding the material, it is heated and melted to bring it into a sheet or film form. Moreover, polyvinyl chloride is the most used material in the process of calendaring.