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CNC machining metal mobile phone shell process flow

2021-07-01
CNC machining metal mobile phone shell process flow
  At present, all metal shells of 3C products are basically processed by CNC machine tools (Computer numerical control machine tools, CNC). CNC has become an indispensable equipment for mobile phone shell manufacturers due to its high efficiency, high precision, and stable processing quality. Many structural engineers may not know the specific processing process and details, just know that it is CNC produced. However, there is no good process without good results. Understanding the processing process will help the smooth progress of the project; this article will introduce all metal The processing process of the middle frame;

Shell manufacturers need to go through multiple processes such as roughing, semi-roughing, semi-finishing, and finishing from programming to obtaining the finished product. In many cases, the whole process requires more than 10 stations to obtain the finished product. If you want to improve the yield rate, each process All need to be strictly controlled.


1. Pre-order work of CNC machining: modeling and programming
Before CNC machining starts, modeling and programming are first required. The difficulty of 3D modeling is determined by the product structure. Product modeling with complex structure is more difficult, and programming procedures are more and more complicated. The programming includes the processing procedure setting, tool selection, speed setting, the distance of each feed of the tool, and so on. In addition, the clamping methods of different products are different, the fixtures must be designed before processing, and some products with complex structures require special fixtures. At the same time, it is necessary to evaluate the size of the blank and the number of CNC. The quality of the preliminary evaluation directly affects the subsequent processing time and processing cost;
2. Mobile phone shell processing technology
2.1 Processing profiles
The cylindrical aluminum material is cut and extruded according to the previously evaluated blank size. This process is called aluminum extrusion, which will make the aluminum material become a regular aluminum plate after extrusion, which is convenient for processing, while being denser and harder;

CNC1: Punching, precision milling positioning hole
Use a CNC machine tool (high-speed drilling center) to accurately machine several positioning holes on the aluminum plate. The positioning datums for subsequent CNC machining are these positioning holes, and the dimensional accuracy of the positioning holes should be controlled within 0.03;

CNC2: Rough milling cavity features
Process the inner cavity and the positioning column combined with the fixture;

CNC3: Milling antenna slot
Metal can shield (weaken) the mobile phone signal, so it must go through the method of slotting, so that the signal has a path in and out;

T treatment
The function of T treatment is to corrode honeycomb holes on the metal surface to enhance the bonding strength of subsequent metal and plastic;
Nano injection
Injection molding materials are generally PPS and PBT

CNC4: Finish milling appearance arc surface

CNC5: Fine milling cavity structure

CNC6: Precision milling USB hole, earphone hole and other structures

CNC7: Finish milling side card holder hole, button hole and other structures

polishing

Sandblasting
The function of sandblasting is to make the metal surface more textured. Different requirements have different sand particles used for sandblasting;
Primary anode
This time the anode is colored;

CNC8: Highlight

Secondary anode
This time the anode is mainly to generate a protective layer, so that the metal performance is not easy to wear;

CNC9: Milling off conductive bits

Anodizing requires all aluminum shells to be turned on, and the anode needs to be milled off to prevent the whole machine from affecting the antenna
At this point, an all-metal shell has been produced;