The rapid development of smart phones also drives the continuous development of the material industry. The sapphire screen, which was the hotspot but not implemented in the past few years, exerts influence on the ups and downs of the entire sapphire industry. The bankruptcy of GT seems to be yesterday. The production capacity of sapphire launched in those years has not yet been used up. Nowadays, the ceramic materials have become the new favorite in the smart mobile phone industry, pulling a new hotspot in the industry.

The perceptual appearance design of smart mobile phone is divided into visual sense and tactile sense. As the name implies, visual sense is the visual effect given by mobile phone, while tactile sense is mainly perceived by hands, which is simply called “hand feel”.

Development history of mobile phone backing plate material

It is developed from plastic, to metal, to glass, and today’s ceramics .Plastic has the advantages of easy processing, light weight, stable properties, and non-conductivity. However, from the perspective of actual experience, compared with other mainstream materials, plastic still lacks a “sense of high grade” in addition to the poor heat dissipation.

Metal: As the most common raw material for metal body, the aluminum alloy is characterized by low density, high strength, strong plasticity, and excellent thermal conductivity. Just in a few years, starting with iPhone 5 launched by Apple in 2012, metal has gone from a flagship device to a thousand-yuan device. The all-in-one process for the aluminum alloy is more complex than that for the plastic; when making a whole piece of aluminum alloy into mobile phone body and frame by CNC and other precise processing steps, it is necessary not only to take into account the RF signal of the mobile phone, but also to cut the metal apart and separate the upper and lower ends by injection, which is the origin of the three-section metal body we usually see. However, until iPhone 5 was launched in 2012, it was something other manufacturers were afraid to try due to the high cost, poor precision control, and the internal wiring and distribution of components in the mobile phone limited by the metal shell, resulting in a undoubtedly higher technical threshold for mobile phone manufacturers. However, as the metal processing technology becomes mature in recent years, these are not a big problem, and the ubiquitous metal thousand-yuan mobile phone is the best proof.

Glass: The mobile phone with glass body not only looks aesthetic, but also has a very delicate sense of touch; it is not too slippery compared with that with metal body. However, glass is not perfect -- it may be used as a fingerprint collector easily, for example – Furthermore, it is impossible to change the fragile property of the glass body, so there is a high risk of breakage. 

Ceramic and other materials: “3D ceramic phone body” is one of the dark technologies used for Mi 5. In fact, Xiaomi is not the first manufacturer who uses ceramic material in the field of mobile phone. 

The common ceramic materials mainly include kaolin, zirconia and so on. OnePlus Phone X in ceramic version uses zirconia. Compared with glass with similar texture, the manufacturing process of ceramic phone body is much more complex. As presented at the official website of OnePlus Mobile Phone, zirconia sand should be subject to grinding and screening, and then a set of key steps such as kneading and granulation, and finally forging at the temperature higher than 1,000ºC. However, the finished product is not completed here. Finally, the material so forged shall be subject to almost 20 processes including rough grinding, fine grinding and polishing of plane, so as to produce the perfect ceramic phone body. 

After setting the above data on the touch screen, start the device to run. DHM-3 stops automatically stops when running to the time so set. Measure the length 12 of the test block after grinding. Calculate the grinding amount AL of the test block.

A L = L I – L 2

If the grinding time is fixed, the larger AL is, the more wear-resistant and sharp the grinding wheel is. The working process of DHM-3 basically simulates the on-site working process of grinding wheel. The test results show that the grinding performance of grinding wheel can be tested by DHM-3 as long as the hard alloy test block with the same quality and appropriate size is selected as the standard test block. Therefore, the grinding performance of the grinding wheel can be truly understood before the product is delivered.

When individual user wants to select and buy very precious grinding wheel in special specifications, the diamond grinding wheel may require the user to provide the ground parts as the standard samples. First, the small sample of grinding wheel shall be made for testing, and the grinding performance indicator shall be submitted to the user; if the operating requirements are satisfied, the large grinding wheel in appropriate specification shall be made, so as to reduce the test cost.

The testing data shall be processed at DHM0’s operation interface of cylindrical measurement record touch screen. On this interface, it is possible to record the working parameters as required; on this status monitoring interface, it is possible to observe and query the testing data in real time.

Conclusion: The result of field use by the user proves that the “grinding performance test method for diamond wheel” proposed in this paper is a practical and scientific test method. We provide a reliable testing equipment for the researchers and manufacturers of diamond wheel process formula, and solve the problem besetting the wheel formula researcher for a long term that it is impossible to quantify and measure the wear resistance and sharpness of the grinding wheel.