With the technical innovation of surface finishing technology, more and more surface finishing technologies have been developed and applied in various industries. It also challenges mechanical design engineers to understand and choose the correct surface fishing process. In this article, we will discuss why choosing the right surface finishing process is important.
Why is a surface finishing important for CNC machining parts?
Surface finishing is an important aspect of CNC machining parts that can affect the function and aesthetics of the final product.
Surface finishing can change the appearance of the parts, make them look more attractive and professional, improve the surface finish, and enhance the overall aesthetics of the parts. To increase their lifespan, some surface finishing processes can provide a protective layer to protect parts from corrosion or damage by environmental factors such as moisture or salt water.
How to choose surface treatments to avoid future problems?
Surface treatment is a process of modifying the surface of a material to enhance its properties. According to the specific requirements of the part and the application situation, the surface treatment of parts will be different. The choice of surface finishing technology will depend on factors such as the material of the part, expected service life, expected surface finish and the application’s specific requirements, such as corrosion resistance, wear resistance, lubrication, adhesion, or aesthetic appearance. Several different surface finishing techniques can be used in CNC machined parts.
A variety of Surface Treatment Selection Guide
Bead blasting: The bead blasting process uses high-pressure air or other abrasive media to clean, polish, or roughen the surface to the desired finish. It is an efficient and versatile surface finish method for mechanical parts. It is commonly used to create a uniform surface with a dull, smooth, or rough texture. It can also remove any remaining burrs or imperfections, and rust is mainly used to improve a part’s visual appearance.
Anodizing: Anodizing is an electrochemical process that creates a protective oxide layer on the part’s surface. Anodizing can improve the part’s corrosion resistance, durability, and appearance. Different types of anodization include transparent, black, and colour anodization.
Anodizing Type I, or chromic acid anodizing, is a surface treatment process used to create a thin oxide layer on the surface of aluminium and aluminium alloys. The thickness of the oxide layer depends on the duration of the anodizing process.
Anodizing Type II (transparent or coloured) adds a corrosion-resistant ceramic layer to the part’s surface. Only available for aluminium and titanium, anodized parts can be dyed in several colours.
Anodizing Type III (hard coating) adds a wear-resistant and corrosion-resistant ceramic layer to the part’s surface. It offers greater protection than type II and can be dyed in different colours. Available only for aluminium and titanium.
Powder coating: Powder coating is a process that involves applying a dry powder to the surface of a part and then baking it to create a durable and decorative finish. Powder coating adds an abrasion and corrosion-resistant finish to the surface of the parts. Compared with anodizing, it is more impact resistant, comes in various colours and can be applied to any metal. Coating resists peeling, fading, scratching and abrasion. This durability makes it ideal for metal parts exposed to sunlight and other environmental factors.
Painting: Painting is a common finishing treatment method for CNC machined parts, including metallic spray painting, Plastic spray painting, Rubber oil painting, UV oil painting, and Imitation leather oil painting. The part is cleaned, primed, and painted with high-quality paint to create a protective and decorative finish. Painting can offer a wide range of colours and finishes, including metallic, glossy and matte finishes.
Polishing: Polishing is a mechanical process that involves removing the surface layer of the part to create a smooth and shiny surface. Polishing can improve the appearance and feel of the part and can also eliminate any imperfections or blemishes during the machining process. Polishing usually includes chemical polishing and hand polishing. Chemical polishing is a quick way to illuminate the surface of a metal part, giving it a shiny look rather than a way to make a perfect surface. Hand polishing is effective for any material, including plastic. It can achieve a mirror polishing grade. However, due to the complex shape of the parts, hand polishing cannot polish narrow areas like grooves and small holes well, which is the biggest disadvantage of hand polishing.
Plating: Plating is applying a thin layer on the part’s surface. Plating can improve the parts’ corrosion resistance, wear resistance and appearance. Different types of plating include nickel plating, chrome plating and gold plating.
Conclusion
In conclusion, surface finishing is a critical step in the manufacturing process that can significantly affect the function and appearance of the final product. It can improve the final product’s performance, durability, and appearance.