Introduction: The process of ceramic backplane is complex, the production is difficult, and the yield is not high. At present, the ceramic backplane technology mainly has differences in technical routes in the molding process. There are four main technologies in the market: injection molding, compression molding, tape casting and isostatic pressing, and the four technical routes have their own merits.
Ceramic molding can obtain a high-density and uniform ceramic body, which is a key link in the preparation of ceramic backplanes, which directly affects the reliability of the ceramic backplane and the final cost. At present, injection molding, compression molding, flow There are four technologies of extension forming and isostatic pressing, and each of the four technical routes has its own merits.
①Injection molding
Injection molding technology is a new process for preparing ceramic backplanes. By adding flow aids to the powder, the mold is filled to obtain the desired shape embryo. It mainly produces ceramic parts with complex shapes and high precision requirements.
Injection molding can be formed near net size. For parts with complex shapes and special requirements, such as backplanes, it can effectively reduce the dependence on CNC machining after sintering, thereby reducing processing costs; injection molding has a high degree of automation and molding cycle. It is short, the obtained blank has high strength, and the production process is easy to manage and control, which is suitable for mass production; in addition, due to the good fluidity of the binder and the small powder gap, the powder and the binder are easy to mix evenly, and the The shrinkage is relatively close, so the density of the formed blank is relatively uniform, the precision of the back plate is high, and the surface gloss is high.
Although injection molding has obvious advantages, it has certain difficulties in feeding formula, mixing and mold development, and the quality of the molding blank is greatly affected by the mold design and the flow state of injection melt filling, so the blank body The larger the size, the less dominant injection molding.
②Compression molding
Molding, also known as dry pressing, is one of the mainstream molding methods for mobile phone ceramic backplanes, and it is also the manufacturing process used for Xiaomi MIX mobile phone ceramic backplanes. It is to pour the powder with good fluidity and suitable particle size into the metal abrasive tool, and use the press to apply external force to rearrange and deform the powder particles, so as to make the desired ceramic embryo.
This method is mostly used in the production of flat high-rigidity ceramic products, which can achieve the effects of low cost, high material utilization, good shearing and recyclability. The dry pressing molding method has the advantages of relatively simple process, convenient operation, short processing cycle but high efficiency, which is conducive to the implementation of automatic production. In addition, the formed green body has high density, high precision, high strength and good electrical properties. However, this process has certain difficulties in the production of large blanks, mainly due to the easy wear of the mold, the complex processing process and the high cost; and due to the fine particle size, light weight and poor fluidity of the powder, the pressure during the upper and lower pressurization process. Products with uneven distribution are prone to cracking and delamination. However, with the gradual development of ceramic backplane forming methods, this shortcoming was gradually overcome by isostatic pressing. In addition, the blanks produced by this method are thick and highly dependent on CNC machining, which increases the processing cost.
③Epilogue
At present, the technical routes of the ceramic backplane process are different, with different advantages and disadvantages, and all products have been applied. However, from the perspective of technical trends, injection molding technology is expected to develop in the long run. The development of technology has provided good conditions for the application of ceramic backplanes, and science and technology have effectively shortened the cycle from production to popularization of new processes.
With the gradual development of the ceramic industry, there is still room for further improvement in the production process of ceramic backplanes in the future. The yield of ceramic backplanes will gradually increase, the production time will gradually shorten, the degree of automation will gradually increase, and the cost will also increase. lower.