CNC machining technology of mobile phone metal shell. In this era of highly valued user experience, more and more manufacturers of mobile phones, laptops and wearable devices start to work on the shell materials. Only from the perspective of mobile phone boundary, mobile phone shell material is also gradually transiting from engineering plastic to metal.
There have been many combination methods in the evolution time of mobile phone shell materials: plastic and metal, glass and metal, all plastic, all glass, etc., but they did not cover the trend of all metal materials. In terms of the essential touch experience, the all metal mobile phone has an outstanding experience in many aspects. It is better than other materials in appearance and feel.
CNC machining
All manufacturers offer all metal shell products
When it comes to all metals, it comes to CNC. At present, all metal shells of 3C products are basically processed by computer numerical control machine tools (CNC). CNC has become a necessary equipment for 3C shell manufacturers because of its advantages of high efficiency, high precision and stable processing quality.
All metal one-piece CNC machining process was initiated by Apple company as early as possible – aluminum plate is die-casting from solid columnar aluminum material. After careful machining, it is cut into the prototype of one-piece fuselage. With the fuselage gradually forming, the keyboard form and various fine structures on the fuselage are milled out. This process includes nine CNC milling processes, after which a well-organized integrated shell can be obtained.
Shell manufacturers need many processes from programming to obtaining molded articles, such as rough machining, semi rough machining, semi finish machining, and finish machining. In many times, the whole process requires more than 10 stations to obtain molded articles. In order to increase the rate of high-quality products, each process needs strict control.
Meizu mx5 obtains shaped articles through 12 processes from right to left
One
Modeling and programming of CNC machining sequence
Before CNC machining, the requirement modeling and programming are the first step. The difficulty of 3D modeling is determined by the product structure. The product modeling with complex structure is more difficult. Programming includes working procedure setting, tool selection, rotation speed setting, interval of each tool feeding and so on. For the rest, the clamping methods of different products are different. Before processing, the clamps should be designed well, and some products with complex structure need special clamps.
Programming includes the processing technology of all products. Although CNC automation is completed in the future, early programming must be operated by experienced staff to prevent repeated trial and error and high cost.
Two
Key processing technology
Using high-speed drilling and tapping center, the aluminum plate is precisely milled into regular three-dimensional volume of certain size, and the next process is planned.
Rough milling: after positioning, rough milling out the inner cavity structure, the positioning column integrated with the fixture, and milling out most of the external redundant raw materials.
Milling the antenna slot: it is difficult to deal with the information problem of the all metal shell. It is necessary to mill out the antenna slot to leave a transmission path for the information and maintain the necessary connection points to ensure the strength and overall sense of the fuselage.
CNC finishing: Finish Milling inner cavity, outer structure, outer surface, side, etc.
Polishing: use high-speed and meticulous CNC machine tool to polish, eliminate knife marks, and plan for subsequent sandblasting.
Sandblasting: it can treat the metal surface into abrasive effect.
Anodizing:
Primary anode: color the mobile phone. Anodizing turns aluminum into gold. At the same time, improve the stability of surface materials
Secondary anode: solid and dense oxide film is formed on the surface of the body, and the wear resistance is further strengthened.
Plastic shell molding using injection molding technology, only need to open mold can be mass produced, yield is very high. While the CNC machining yield of all metal fuselage is determined by the complexity of the shell structure and the accuracy requirements. It is difficult to reach the high yield of plastic shell. In order to average high cost, most manufacturing enterprises will choose to purchase a large number of CNC equipment to reduce the comprehensive cost and reach the production rate in the face of value war.
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