Looking at the future of mobile phone appearance materials from the release of the new iPhone - the value of the middle frame of the mobile phone is prominent, and the era of liquid metal middle frame is coming.
Recently, Apple held a new product launch conference at the Jobs Theater, which launched iPhone 8, iPhone 8 Plus and iPhone X, as well as the third generation of Apple Watch and other products.
This time, Apple skipped the previous S enhancement series and directly launched the iPhone 8/8 Plus. The main change in appearance is that the back cover is replaced with a glass panel, which is officially called the strongest and most durable glass panel so far. The back tempered glass is finished with a 7 layer stain process. With it, there is a new gold color matching in addition to space gray and silver; after replacing the metal material of the previous generation with glass, the iPhone 8 is still 7000 series aluminum as a metal middle frame.
iphone X
Official release date: November 3, 2017
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Of course, the most eye-catching is the iPhone X (Ten) that debuts as one more thing, which Apple officials say is the future of the smartphone in the next 10 years.
Its biggest highlight is that it is rumored to unanimously adopt the "full screen" design and use OLED material for the first time. It uses innovative folding and circuit stacking technology, so that this OLED screen can accurately fit the curve of the body in the form of a full screen, so as to achieve a satisfactory round touch.
Like the iPhone 8/8P, the iPhone X has a glass panel on the back cover, which is the strongest and most durable glass material on the iPhone so far. Its reinforcement layer is 50% thicker than before.
Unlike the former, the iPhone X replaced the middle frame material and the 7 series aluminum alloy with stainless steel, which Apple called "surgical grade". In addition, on the space gray model, the "physical vapor deposition" process is still used to ensure that the color of the stainless steel frame is consistent with the glass color.
Every time Apple uses a new process, it will become a vane for mobile phone development. This time, Apple's return to the appearance material matching of double-sided glass + metal middle frame will lead the transformation of the whole industry.
The appearance material and structural change history of iPhone
The future development trend of mobile phones brings changes to mobile phone structure and materials.
1. Full-screen technology is popular
The full screen is called the last technological innovation point of the mobile phone industry before the arrival of 5G. The reason why full-screen has become an industry hot spot is mainly that full-screen products are more in line with users' needs for video playback and display interface. The benefits of using a full-screen mobile phone are self-evident. The first is to maximize the visual effect, and the second is to optimize the grip.
Because of the full screen design, the screen module will extend to the upper and lower ends of the whole machine, which will greatly reduce the main net space left for the antenna. If the metal shell is still used, the mobile phone signal will be greatly affected. At the same time, the borders on all sides will become narrower and narrower, and the requirements for the strength of the frame in the mobile phone will also be higher and higher, and the requirements for falling and pressure resistance will be higher.
Because of the full screen design, the screen module will extend to the upper and lower ends of the whole machine, which will greatly reduce the main net space left for the antenna. If the metal shell is still used, the mobile phone signal will be greatly affected. At the same time, the borders on all sides will become narrower and narrower, and the requirements for the strength of the frame in the mobile phone will also be higher and higher, and the requirements for falling and pressure resistance will be higher.
2. Wireless charging is gradually mature, and the iPhone has become a tipping point.
With the iPhone 8/8P this time, the iPhone X is standard with wireless charging, which is bound to promote the wide application of wireless charging in smartphones. However, due to the shielding effect of the metal case, mobile phones with metal bodies generally cannot support wireless charging function. Even if this function is added, their wireless charging efficiency will be greatly reduced. Therefore, if mobile phone manufacturers follow Apple's example and add wireless charging function to new phones in the future, they will inevitably give up the metal shell and use glass or ceramic shells instead.
Because of the full screen design, the screen module will extend to the upper and lower ends of the whole machine, which will greatly reduce the main net space left for the antenna. If the metal shell is still used, the mobile phone signal will be greatly affected. At the same time, the borders on all sides will become narrower and narrower, and the requirements for the strength of the frame in the mobile phone will also be higher and higher, and the requirements for falling and pressure resistance will be higher.
3. In the future, 5G mobile phones will dominate the absolute mainstream.
5G is undoubtedly the focus of the mobile phone industry. For smartphones, improving load computing and supporting various scenario applications to improve the full-scene experience ability will become the focus of the next stage of development during the migration of 4G to 5G.
It is expected that the global sales of 5G mobile phones will reach 100 million by 2021, and the mainstream 5G mobile phone market will be in developed countries in North America and Asia-Pacific.
The remarkable feature of 5G signal is that the signal transmission speed is faster (10-100 times that of 4G), which greatly facilitates people's lives!
However, 5G also brings at least two changes to the structure of mobile phones: first, due to the addition of 5G signals, mobile phones have more RF functions and larger volume, requiring new internal component design; second, 5G puts forward higher requirements for the signal transmission capacity of mobile phone shells, and large-scale MIMO promotes the base stations to use multiple antennas. The complexity of its antenna makes the appearance material type of mobile terminal equipment require a trend of transformation from metal to non-metal.
Under the trend of 5G communication, wireless charging and full screen, the process of demetallization of the appearance of mobile phones has begun. The trend of demetalization will reconstruct the entire mobile phone appearance industry value chain. Under the leadership of Apple, the appearance structure of mobile phones has developed from monomer to "sandwiches", and the double glass/ceramic + metal middle frame scheme of appearance materials will become the mainstream.
Glass ceramic back cover triggers market fusion
The value of the middle frame of the mobile phone is prominent.
2.5/3D glass has a very beautiful appearance and texture, which is expected to become an important back cover solution. In addition, after years of development, the performance of glass materials has been greatly improved;
In terms of cost, the yield of 2.5D glass is relatively high, with a price of about 25 yuan and a price of 3D glass of about 75 yuan, which has a significant cost advantage over other ceramics, sapphire and other non-metallic materials. In terms of production capacity, glass processing capacity is not scarce, and there are many existing manufacturers and potential entrants. Glass floor is the first to popularize with comprehensive advantages such as performance, cost and production capacity.
The electromagnetic performance under 5G of ceramic materials has obvious advantages, such as wear resistance, skin-friendly, good airtightness, good electromagnetic shielding, excellent performance, and is favored by mobile phone manufacturers. At present, it is subject to cost and production capacity. As a large-scale enclosure product, it is still a niche application. The reduction of cost brought about by the improvement of ceramic material technology level is the key. With the improvement of yield and production capacity, it is expected to become one of the mainstream non-metallic materials.
Under the new situation, the design route of double-sided glass/ceramic + metal middle frame in the future is in a dominant position, and the penetration rate of middle and high-end brand mobile phones has gradually improved. The industrial trend of new material back cover + metal middle frame will highlight the value space of metal middle frame products. The middle frame of the mobile phone is an important part in the structure of the sandwich of the mobile phone. It supports and carries the key parts of the core components. It has many requirements in terms of strength, structure, heat dissipation and other aspects.
The dispute over middle frame materials
Liquid metals become the mainstream
Aluminum alloy has always played the leading role in the middle frame material of mobile phones, but with the requirements of full-screen technology, wireless charging and 5G, the space requirements for the metal middle frame are getting narrower and narrower, and the strength requirements for the metal middle frame are also higher. Aluminum's protection against glass is insufficient, and its own strength is not enough to make it easy. Deforming squeezes the glass, causing the glass to be fragile.
Comparison of performance of aluminum alloy and stainless steel middle frame
Compared with stainless steel or aluminum alloy middle frame, liquid metal has performance and price advantages. The strength of liquid metal frame is much higher than that of stainless steel and aluminum alloy. The most obvious advantage of this material is high strength, high hardness and high wear resistance. While light and thin, it can also protect the mobile phone from shocks and screen breaks. Damage.
In addition, liquid metals are molded once by injection molding, which can meet the molding requirements of some complex structures. Because its molding process is close to "net forming", it requires fewer post-processing, which can effectively reduce the post-processing cost. At present, the price of a liquid metal mobile phone is about 120 to 150 yuan, which is cheaper than the stainless steel frame and aluminum alloy integrated molding frame.
Analysis of the advantages and disadvantages of liquid metals and stainless steel
1. Net molding technology
1) Liquid metal molding process is simple, process stability is strong, consistency is good, and the process yield can reach more than 85%.
2) The molding cycle is 70s~90s, with a high production capacity, and each machine can produce 1,000pcs a day.
3) Because mold molding can accurately control the deformation of the product, the later process can meet the plane degree requirement without shaping. In addition to the above 11 forging processes, the stainless steel process needs to add at least 3 tempering processes, and it is still difficult to ensure a plane degree of 0.1.
4) The processing allowance is only 0.15mm~0.2mm, which greatly reduces CNC time, improves the efficiency of the post-process and reduces the cost.
5) Adopt vacuum molding technology, the surface dense layer is thicker, generally up to 0.3~0.4mm, polishing process can be achieved.
2. Streamlined CNC
Comparison of CNC machining cycles of stainless steel and liquid metal
Liquid metals adopt net molding technology, and the CNC time is only 40% to 50% of the stainless steel scheme. If some product structure is optimized from the design stage, the CNC time can be controlled within 1200s.
3. Comparative analysis of the whole process of liquid metal and stainless steel
The full-screen and wireless charging trend led by the iPhone, especially the arrival of the future 5G era, liquid metals with excellent performance and cost advantages have matured a wide range of application conditions on the middle frame of mobile phones, and liquid metals will become one of the mainstreams of terminal devices in appearance materials.
At present, some domestic enterprises and units have the R&D and production capacity of liquid metal mobile phones, including Yi'an Technology, Dongyu Yihao, Changzhou Shijing, Liaoning Jinyan, etc.
The figure below shows the middle frame prototype of liquid metal of Yi'an Technology. As an early enterprise in the industry to carry out liquid metal research and development, Yi'an Technology has the world's largest production line for the production of zirconium-based amorphous alloys, and has achieved industry-leading advantages in the application research and industrial transformation of block amorphous alloys. At present, the company has provided many well-known domestic mobile phone brand manufacturers with samples of liquid metal mobile phone middle frame.
