Shanghai Elue is professional in CNC turning and machining. Except CNC machining done in-house, we also add various finishes to make them perfect.
Firstly, let's check out the definition of surface finish. It is the measure of the texture of a part’s surface that is described by three attributes including surface roughness, waviness, and lay. It’s a process that can change a surface by removing, adding, or reshaping it.
The main objective of finishing the product is to achieve certain attributes and functionalities like enhanced aesthetic appeal and appearance, to render additional strength and wear resistance, improve conductivity, or protect against chemical reactions, etc.
Now let's see what options we use to finish CNC machined parts?
Polishing is done to achieve a smooth and shiny surface. Surface is rubbed or applied with a chemical treatment that yields a clean surface with a significant specular reflection. It can also reduce diffuse reflection of some materials to minimum.
Polishing technology is mainly used in precision machinery and optical industries. The surface of the polished CNC component or workpiece is smooth and has a good reflection effect.
There are 3 types of polishing Process, one is mechanical polishing which is mainly done by manual operations, and the surface roughness can reach 0.82μm through this way; the other process is Chemical polishing, Chemical polishing is a method that relies on the chemical leaching effect of chemical reagents on the uneven area of selective dissolution to eliminate abrasion marks, leaching and leveling. This type polishing equipment is simple, capable of handling thin tubes, with deep holes and complex-shaped parts, high productivity.
The last one often used is Electropolishing. It is used to remove unwanted micro-peaks from metals surface. It is an electrochemical process used to level tiny peaks on the surface and ameliorates surface roughness.
In the industrial production of stainless steel machining, aluminum machining, non-ferrous metals and ferrous metals precision machining, electropolishing has become one of the indispensable surface finishing methods. and the surface roughness of 0.3μm can be achieved.
Beadblasting is widely used in cnc machine aluminium parts. This finishing technique is used to clean part's surface and refine the overall appearance that creates a homogeneous surface with a rough or dull texture. Bead blasting is a type of shot blasting that involves shooting high-pressure materials (glass or steel) beads at parts surface.
If you're worried about dimensional changes, the critical features like holes can be masked before blasting. And beat blasting is mainly used for visual purposes and it is a manual process meaning that the results may differ depending on the skills of the operator.
The pros of blasting are a uniform and textured finish and it is a relatively low cost surface finish. The cons are that it's a manual process and it can influence dimensional tolerances and surface roughness. To conclude, bead blasting is used to create a matte uniform finish when dimensional tolerances are not a key concern.
Plating means applying a thin coating of metal. In this method a metal is deposited on a conductive surface. Electroplating helps to improve the strength, durability and life span of metallic parts. There most often used ones include nickel plating/ chrome plating/ tin plating/ silver plating.
Plating can be used for a range of metal materials, like cnc steel machining, spring steel cnc machining, cnc machining stainless, etc.
Anodizing is an electrochemical passivation process that provides anodic oxide finish. It introduces surface durability, aesthetics, and improved corrosion-resistance. It uses aluminum as anode and elevates natural oxide layer on the surface, and it’s especially popular for cnc machine aluminium parts.
We normally use Type II anodizing, it's mainly used to enhance their looks, known as “decorative anodizing”. Type III is also available here for surfaces that need to be extra hard. So it's also known as “Hard Coat Anodizing”. Parts with this coating have high density and have even more wear-resistant than anodizing Type II.
Powder coating is such a finishing method in which dry, free-flowing, thermoplastic, or thermoset powder material is applied (electrostatically) to a surface and then cured under heat or with ultraviolet light. It helps to achieve great product finishes in respect of functionality and appearance.
Unlike anodizing, a powder-coated finish is compatible with all metals, less brittle, and offers greater impact resistance. This finish is suitable for many functional applications but may be particularly well-suited for military applications.
The first thing we do is meeting with our clients and talk through their goals on a future project.
During this meeting, feel free to communicate your ideas and ask lots of questions.
Copyright © 2022 Shanghai Elue Industrial Co.,Ltd All Rights Reserved.