In the field of smartphones, the content of mobile phone canning has already shifted from engineering plastics to metal materials and has even become the standard of a hundred yuan machine body. In the process of evolution, the change in the physical material has changed. It has tested all plastic, plastic, and metal, glass and metal mixing methods, but in the end, they prevent the all-metal body from joining the mainstream. I failed. Although there are now many combinations of metallic middle frame + glass / ceramic back cover, Ultimate Metal Body is still the choice of most mobile phone manufacturers in the industry, and will continue to be available in the next few years, without real experience or The impression doesn’t matter. In terms of the metal body, it has unique advantages.
On the introduction of smartphones with metal bodies in general, we will see: The xxx mobile phone’s rear shell is processed by CNC, oxidation, polishing, sandblasting, and other XX precision technologies. I think many small partners don’t understand it. Whenever I see these words, I ask: What exactly are these processes doing? How is the All Metal Body “Improved”? Today, I will talk to you about the secret of processing the metal body of mobile phones.
Before understanding mobile phone fuselage processing technology, let’s first understand the advantages and disadvantages of the metal fuselage:
Advantages: Metallic luster, excellent feel, compression, and bending resistance, scratch resistance, and scratch resistance
Smartphones with metal bodies have a unique metallic shine and good grip, while the unique cold features of metals can provide better heat dissipation to the body, and mobile phones made of the magnesium-aluminum alloy will be lighter, lighter than the plastic body. Also, but it can ensure the body’s rigidity, its tensile, compression and bending capabilities far outweigh the plastic body.
Currently, mobile phone manufacturers hope to thin the cellphone and tighten the frame. Therefore, the metal body has also become the first choice for narrow frame / ultra-thin mobile phones, such a design is bound to place more requirements on the metal body. Also, metal has more strength than plastic and is much stronger than plastic or other materials (such as ceramic) in terms of scratch resistance and scratch resistance.
Disadvantages: Difficult processing, color difficulty, signal difficulty
Plastic body processing is very simple. It only requires a mold to form to complete the processing, while metal body processing and painting process through CNC, oxidation, polishing, sandblasting, and other precision processes. Is brought in In terms of processing time and technical difficulty, metal body processing is more complex.
To be clear, the biggest drawback of the metal body is the signal problem, which is why the “Leucadia” that some consumers want to ask for cannot be canceled. The author describes it briefly here because the good conductive properties of the metal greatly affect the performance of mobile phone antennas, so only the use of non-conductive media to isolate the metal to pass the signal well. Can be done This ensures normal Internet access and communication. Use, now mobile phone manufacturers are also making great efforts to hide “leucorrhea”, such as top, bottom, groove, and other processing, its effect is not particularly satisfactory.
After understanding the benefits and disadvantages of a metal body, let’s talk about the metal body process:
1. Aluminum emission, DDG, rough milling inner cavity
First, the aluminum material needs to be cut and rolled out to form an aluminum plate (dense and hard). The actual aluminum material is not rigid and solid. The mobile phone’s body is usually made of aluminum alloy. This material also has different properties according to different formulas. For example, the iPhone was the 6000 series aluminum alloy material 6 is not so strong, and it is too much bending.
Then, the aluminum alloy plate is mounted to the required size for the mobile phone body, which is easy for CNC precision machining. Then, the inner cavity is somehow found, and the inner cavity and fact-fixing pillars are processed, which play a definite role in precision machining.
2. Milling antenna slots, T-processing, nano-injection molding
The biggest drawback of the metal body is the disturbance of the signal, so the metal body must be slotted first so that the signal goes in and out. The next step is the T treatment of the antenna slot model. The metal body is placed in a special T liquid chemical agent, to form a nano-scale cavity on the surface of the aluminum alloy, which is easier for nano injection. The special material of plastic is squeezed into the T-treated groove. (Some mobile body injections are added later)
3. Excellent milling arc level and precision milling side
After the nano-injection molding is finished, the metal material surface requires action, ie 3D molding of the mobile phone body. After this process, the basic shape of the mobile phone body is processed as well.
4. Polishing and sandblasting
The use of high-level high-precision CNC machine tools will allow the metal body to reach A1 ~ A2 level, which is quite far. The body must reach the A0 level through the polishing process. After the step, the mirror effect can be achieved. After that, the metal surface is processed into a blurred effect. The process of blasting is to achieve the level of light decoration of the film or to achieve excellent reflective surface to meet the requirements of special design such as soft glow.
5. Primary anode, high gloss processing (diamond cutting), precision milling of the inner cavity
To prevent the metal body from being affected by sweat and other external factors and to improve its durability, it must be immobilized. At the same time, it is also a process of colorizing the mobile phone body. The deodorization of aluminum is the metal surface through the current process. Made of a layer of an oxide film, rich color, beautiful color, and good electrical insulation of rigid wear resistance, corrosion resistance high.
After passing the first level of the inode, you need to drill holes for volume keys, speakers, etc. After opening, use the highest ultra-high-speed CNC machine to cut corners. With a high degree, thick and thin knife pattern, using the principle of anxiety, the decorative effect can be greatly enhanced. After high-throughput treatment, the positioning column used to correct the inside is expected to be removed. This is the precision milling of the inner cavity.
6. The second anode, the milling position
This is followed by second insulation from the outside of the metal body to form a dense and rigid oxide film on the surface of the shell to ensure body wear and stain resistance. The conductivity of the anodized aluminum alloy shell will be poor, so removal of the local anodized film is necessary, and the exposed metal has achieved a good ground effect, and the CNC treatment of the conductive position needs to be reunited.
7, hot-melt nuts
The processing is done here, and finally, the assembly nut is intended to be injected into a molded plastic that can be fixed using a robot to fit the motherboard or other components.
After going through the aforementioned process, eventually, a piece of aluminum alloy has been transformed into a beautiful mobile phone case. Of course, the order of some matters may vary.
Looking at it everyone will realize that CNC isn’t so mysterious. It’s true. CNC CNC is a summary of machine tools: computer numerical control machine tools. The easiest computer-controlled digital machine tools. If there is a difference, this can only be the difference in the precision of the processing. For mobile phone metal matters, the precision of the processing is not much. The corresponding micrometer is calculated in thousands of parts. It’s a lot worse than that. All in all, the process of mobile phone metal matters is not mysterious, what do you think?