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Surface Treatment Methods In CNC Machining

In the vast world of manufacturing, surface treatment is crucial after CNC machining. It not only beautifies the appearance of the product, enhances wear resistance and corrosion resistance, improves accuracy and extends service life, but also meets the needs of different application scenarios through customized processing, significantly improving product-added value and market competitiveness. This article will give you an in-depth understanding of surface finishing methods in CNC machining, and explore the principles, advantages, selection basis, etc. of various machining technologies.

Surface Finishing CNC Machining parts

What Is Surface Finishing?

Surface finishing, also known as surface technology, is to change the surface state, chemical composition, organizational structure and stress state of the workpiece through mechanical, physical or chemical methods, or to apply various covering layers, so that the surface of the workpiece has some special characteristics different from its matrix. Performance, an application technology that meets specific usage requirements.

Why Is Surface Finishing Important?

CNC machining lays a solid foundation for the product and provides a solid inner structure. Surface treatment is a detailed optimization and enhancement of this solid foundation. It not only involves fine cleaning, deburring, grease removal and other pre-treatments on the surface of the workpiece, but also improves the appearance of the product through scientific physical or chemical treatment methods, such as uniform gloss and natural color presentation, and is also effective Improved product durability and corrosion resistance.

Our Surface Finishing Services

From precision machining to comprehensive surface treatment services, we offer more than 40 surface finishing options designed to meet your diverse needs for corrosion resistance, wear resistance, aesthetics and extended service life. In order to ensure the excellent quality of each CNC machined part, we strictly implement 12 quality inspection processes to ensure that the yield rate of finished products is as high as 98%, so that you can trust every detail of the product.

CNC Machining Parts Surface Finishing Services

Commonly Used Machining Methods After CNC Machining

Anodizing

Principle: The metal is placed in the electrolyte and used as an anode, and an oxide film is formed on the metal surface through electrolysis.
Application: Commonly used for surface treatment of aluminum and its alloys to improve corrosion resistance, wear resistance and hardness, while giving it a specific color and luster.

Anodizing

Sandblasting

Principle: Use the impact of high-speed sand flow to clean and roughen the surface of the substrate.
Application: It is often used to clean dirt, oxide scale, etc. on the surface of workpieces, while improving the surface roughness and adhesion to prepare for subsequent machining such as spraying, electroplating, etc.

Sandblasting cnc machining parts

Polishing

Principle: Use mechanical, chemical or electrochemical effects to reduce the surface roughness of the workpiece to obtain a bright and smooth surface.
Application: Commonly used for surface finishing of metals, plastics and other materials to improve appearance quality and corrosion resistance.

polishing cnc machining parts

Brushed

Principle: Lines are formed on the surface of the workpiece through grinding to achieve a decorative effect.
Application: Commonly used for surface finishingt of metal materials, such as aluminum alloy doors and windows, stainless steel kitchenware, etc., to enhance the aesthetics and texture.

Brushed cnc machining parts

Plating

Principle: Use the principle of electrolysis to plate a thin layer of other metals or alloys on certain metal surfaces.
Application: Widely used to improve the corrosion resistance, wear resistance, conductivity and aesthetics of materials, such as chrome plating, nickel plating, gold plating, etc.

plating

Electrophoresis

Principle: Under the action of an electric field, paint particles are deposited on the workpiece to form a film.
Application: Suitable for uniform coating of complex-shaped workpieces with good adhesion and corrosion resistance.

electrophoresis cnc machined parts

Powder Coating

Principle: Under the action of the electric field, the paint particles are electrostatically attracted and deposited on the surface of the workpiece, gradually forming a uniform coating film.

Application: Powder spraying is suitable for uniform coating of complex-shaped workpieces, and the coating film formed has good adhesion and excellent corrosion resistance.

Water Transfer Printing

Principle: Water transfer printing uses water as a medium to transfer the pattern to the surface of the substrate through the pattern on a special carrier (such as a film) under the action of an activator.

Application: This technology is widely used in many fields, especially in the automobile and motorcycle industries. It provides a variety of personalized decoration solutions for parts such as wheels and fuel tank caps; at the same time, in home decoration, electronic products and cosmetic packaging, water transfer printing technology also plays an important role.

Water transfer printing

What are the Advantages and Disadvantages of Surface Finishing?

Advantage:

Improve material performance: Through surface treatment, the corrosion resistance, wear resistance, hardness, electrical conductivity, thermal conductivity and other properties of the material can be significantly improved, thereby extending the service life and reliability of the product.
Improve appearance quality: Surface treatment can improve the appearance quality of materials, such as gloss, color, texture, etc., making products more beautiful and attractive.
Enhance adhesion: Certain surface treatment methods, such as sandblasting, chemical treatment, etc., can increase the roughness of the material surface, thereby improving the adhesion of the coating or plating, making the coating stronger and more durable.
Reduce maintenance costs: By improving the material’s corrosion and wear resistance, surface treatment can reduce product maintenance costs and reduce the frequency of replacement and repairs caused by corrosion, wear and other issues.

Disadvantages:

Cost increase: Surface finishing usually requires additional equipment and materials, as well as professional technicians to operate, thus increasing the manufacturing cost of the product.
Environmental impact: Certain surface finishing methods, such as electroplating, spraying, etc., may produce harmful substances and waste, causing pollution and harm to the environment. Therefore, when performing surface treatment, corresponding environmental protection measures need to be taken to reduce the impact on the environment.

Conclusion:

Surface finishing is an important step after CNC machining. It improves the surface properties of materials through physical or chemical methods to meet the needs of different industries for product performance, appearance and durability. This technology is widely used in automobiles, optics, automation, medical and other fields, providing reliable and effective solutions for the manufacturing industry.

FAQs About Surface Finishing

Surface finishing and surface coatings are both used in manufacturing to improve the surface properties of materials, but there are differences. Surface finishing is a broad process concept, including mechanical, chemical, electrochemical and other methods, in order to give the material surface-specific properties or functions, such as corrosion resistance, wear resistance or decoration. Surface coating is a specific form of surface treatment, which specifically refers to the formation of a covering layer with specific functions on the surface of the material. This covering layer can be made of metal, ceramics or polymers.

Metal surface finishing includes mechanical finishing (such as sandblasting, polishing, drawing), chemical finishing (such as phosphating, pickling) and electrochemical finishing (such as electroplating, anodizing) as well as modern technologies such as physical vapor deposition (PVD) and chemical vapor deposition (CVD). These methods aim to improve the properties of metal surfaces such as corrosion resistance, wear resistance, electrical conductivity and aesthetics.

One of the easiest ways to blacken metal is to use vinegar and baking soda. Mix an appropriate amount of baking soda and vinegar until foam forms, then apply this mixture to the metal surface that needs to be blackened and wipe it clean with a clean cloth. This method works on a variety of metals, such as aluminum, copper and stainless steel.