Smartphones, LCD TVs, computers, cars, and other products all use numerous cutting-edge technologies, and ceramics are equally indispensable among them. For example, there are hundreds to thousands of miniature electronic components used in a smartphone - ceramic capacitors. But these types of ceramics are not common "tiles" or "bowls" in people's lives. They are advanced ceramics produced using high-precision technology.

1.Classification of ceramics

        Ceramic products are divided into two categories: ordinary ceramics and advanced ceramics. Among them, advanced ceramics, also known as new ceramics, special ceramics, fine ceramics, high-tech ceramics, etc., refer to ceramics that use high-purity, ultra-fine artificially synthesized or selected inorganic compounds as raw materials, have precise chemical composition, precise manufacturing and processing technology and structural design, and have excellent mechanical, acoustic, optical, thermal, electrical, biological and other characteristics. They can be seen everywhere in high-end technology fields such as aerospace, electronic information, biomedicine, and high-end equipment manufacturing.

2.Classification and Application of Advanced Ceramics

        Advanced ceramics are divided into two categories: structural ceramics and functional ceramics. Structural ceramics refer to ceramics that can be used as engineering structural materials, with characteristics such as high strength, high hardness, high elastic modulus, high temperature resistance, wear resistance, corrosion resistance, oxidation resistance, and thermal shock resistance. Functional ceramics are a type of ceramic with electrical, magnetic, optical, thermal, chemical, biological and other characteristics, as well as mutual conversion functions. Functional ceramics account for approximately 70% of the market share in advanced ceramics, while the rest are structural ceramics.

（1） Electronic ceramics

        With the rapid development of the information technology industry and electronic consumption industry, industrial electronic products and consumer electronic products will maintain a rapid development trend, and there is a huge demand for electronic ceramics. It is expected that the global demand for electronic ceramics will exceed 40 billion US dollars by 2020. Electronic ceramics are the most mature technological product among advanced ceramics, accounting for 65% of the market share of advanced ceramics. Mainly used for packaging chips, capacitors, integrated circuits, sensors, insulators, ferromagnets, piezoelectric ceramics, semiconductors, superconductors, etc. The main materials include barium titanate, zinc oxide, lead titanium zirconate, lithium niobate, aluminum nitride, zirconia, and aluminum oxide.

（2） Bioceramics

        Bioceramics refer to ceramic materials that directly act on the human body or are related to biology, medicine, biochemistry, etc. Generally speaking, ceramic materials belonging to bioengineering are collectively referred to as bioceramics. As a bioceramic material, it should have the following functions: replacing diseased or damaged parts in the human body, as a substitute for congenital defects in the human body, and helping to restore tissues in the human body.

        Biomedical materials have become a hot topic for scientists from various countries to research and develop. 70% -80% of domestic biomedical materials and products rely on imports and are basically imitations. China's biomedical materials only account for 2% of the global market share, and the product technology level is mostly in the early stage. With the aging population, by 2020, China will require 800000 sets of artificial joints per year, 1.6 million vascular stents per year, and 1.4 million intraocular intraocular intraocular lenses per year, leading to a significant increase in demand for bioceramic materials.

        In addition to being used for measurement, diagnosis, and treatment, bioceramics are mainly used as substitute materials for biological hard tissues and can be applied in various fields such as orthopedics, plastic surgery, oral surgery, cardiovascular surgery, ophthalmology, otolaryngology, and general surgery.

（3） Nano ceramics

        In recent years, nanoceramics have received great attention from people. When the selected raw materials and the resulting grains reach the nanoscale, it will bring about a sudden change in the preparation science, ceramics, ceramic technology, and ultimately material properties of ceramic materials, thus opening up a wider range of applications for ceramic materials.

        At present, there are three main types of preparation methods for nanoceramics: physical preparation method, gas-phase method, and wet chemical method. The prepared nano ceramic powders include Al2O3, ZrO2, SiO2, Si2N, SiC, BaTiO3, TiO2, etc. The development of nanoceramics has driven the development of some new rapid sintering equipment, such as vacuum sintering process, microwave sintering process, and plasma sintering technology (SPS).

（4） Low expansion ceramics

        The absolute value of the coefficient of thermal expansion is less than 2 × 10/ Materials with a temperature of ℃ are called low expansion materials, while materials with a coefficient of expansion close to zero are called ultra-low expansion materials. Low expansion ceramics, especially zero expansion ceramics or negative expansion ceramics, can be used as the main components of engines, aviation material blades, furnace gaskets, circuit substrates, astronomical mirror blanks and antenna covers, high-temperature observation windows, precision measurement devices, carriers and filters, nuclear waste fixation, sealing materials and other high-tech materials.

（5）Advanced ceramics used in energy conservation, environmental protection, and new energy fields

        With the rapid development of the economy and the rapid increase in energy demand, a huge amount of industrial and domestic waste is generated. Energy conservation and environmental protection have become major issues of increasing concern to the international community. In the context of energy scarcity and increasingly severe environmental degradation, advanced and efficient energy-saving and environmental protection technologies will be able to achieve energy-saving thermal waste incinerators (RT0), as well as honeycomb ceramics for energy-saving heat storage chambers in the smelting industry, ceramic membranes and equipment for hot gas purification and water treatment, series of ultra-high voltage suspension ceramic insulators for ultra-high voltage AC transmission technology and equipment, silicon carbide ceramic components for heat storage and exchange, and series of ceramic products for photovoltaic industry, all of which will have rare development opportunities.

（6） Aerospace ceramics

        The application mainly involves bulletproof armor ceramics for helicopters, aircraft brake disc materials, ceramic diaphragm materials for satellite batteries, infrared stealth (camouflage) coatings, ceramic bearings, ceramic antenna cover materials for missiles, etc. At present, the application research in aerospace mainly focuses on heat-resistant materials for rocket nozzles, insulation tiles for spacecraft, composite engineering ceramic materials, and observation window coatings for spacecraft, especially the research and development of ceramic fibers with lightweight, heat-resistant, ablation resistant, high melting point, and high strength.

3.The military industry has become a hot market for advanced ceramics

        Functional ceramics account for approximately 70% of the market share in advanced ceramics, while the rest are structural ceramics. The military applications of ceramic materials mainly focus on structural materials and electronic devices:

（1）Used for aviation engines and aircraft brake discs

        For aircraft engines, increasing the temperature of the gas in front of the turbine is the main technical way to increase engine thrust. However, the current temperature of the gas in front of the turbine is gradually approaching the melting point of the high-temperature alloy itself, and there is little room for temperature increase. Therefore, alternative materials are needed. Ceramic matrix composites have high temperature resistance and can be used for hot end components. Research has shown that ceramic matrix composites can increase the gas temperature in front of the turbine by more than 300K on the existing basis. At the same time, ceramic matrix composites have a low density, which is beneficial for engine weight reduction. With the continuous pursuit of improving fuel efficiency in the civil aviation industry, General Aviation GE expects the application of ceramic matrix composites in aviation to increase tenfold in the next decade.

（2）Used in aircraft brake disc materials

        Compared with the previous generation of brake discs, carbon ceramic brake discs have a 1-2 fold increase in static friction coefficient, a 60% reduction in wet friction performance degradation, a 50% reduction in wear rate, and a 1-2 fold increase in service life. Reduce production cycle by 2/3, production cost by 1/3, energy consumption by 2/3, and cost-effectiveness by 2-3 times. It is currently the only material found internationally that can maintain all physical properties without degradation in a high-temperature environment of 1500 ℃. After promotion and application, it can save about 300 million yuan in costs for Chinese civil aviation aircraft annually.

（3） Used for thermal structural components of rocket engines

        Ceramic matrix composites can be used in rocket engines. Due to its high heat resistance and impact resistance, ceramic matrix composites have high chemical stability for liquid propellants, are more resistant to high temperatures than metal materials, and have higher creep resistance. They are an ideal material for thermal structural components of liquid rocket engines.

（4）Thermal protection materials for spacecraft and missiles

        During the process of spacecraft entering the atmosphere, due to strong aerodynamic heating, the temperature of the nose cone and wing leading edge of the spacecraft can reach up to 1650 ℃. Thermal protection system is one of the key technologies of spacecraft. The design of the first generation thermal protection system adopted the idea of separating heat release and structure, that is, adding an exothermic system to the external cooling structure. The development of C/SiC composite materials has integrated the load-bearing structure and heat release of aircraft. Especially after the failure of the thermal protection system on the Columbia, which resulted in machine crashes and fatalities, C/SiC ceramic matrix composites have attracted more attention. The components of thermal structural materials include the nose cones, guide wings, wings, and cover plates of space shuttles and missiles.

（5）Used for satellite reflectors

        The performance requirements of satellite reflector materials include low density, high specific stiffness, low coefficient of thermal expansion (CTE), high thermal conductivity, appropriate strength and hardness, and designability. Both glass mirrors and metal mirrors have certain limitations when processed into large and lightweight mirrors. Therefore, both domestically and internationally, research is being conducted on C/SiC composite reflective mirrors. This composite material has a low density, high stiffness, low coefficient of thermal expansion at low temperatures, good thermal conductivity, ideal thermal and mechanical properties, and can achieve excellent surface polishing. It is a perfect satellite reflector base material. The United States, Russia, Germany, Canada, and others have used carbon fiber reinforced silicon carbide composite materials (Cf/SiC) to prepare high-performance mirrors.

（6）Ceramic materials and ceramic matrix composites will be used in armor

        Such as bulletproof vests, protective layers for fighter jets and armored vehicles. A bulletproof vest mainly consists of a jacket and a bulletproof layer. The bulletproof layer can absorb the kinetic energy of a bullet or fragment, and has a significant protective effect on low-speed bullets or fragments. It can reduce damage to the chest and abdomen of the human body by controlling a certain degree of indentation. Hot pressed boron carbide and silicon carbide ceramic matrix composites can be used to manufacture sturdy armor plates that resist impact. China is one of the three largest producers of bulletproof vests in the world. In the international market, the price of our defense bulletproof vests is about $500, while the price of bulletproof vests in other countries is around $800. China has an advantage in manufacturing costs.

（7） Used in aircraft armor

        Some military helicopters are equipped with ceramic armor systems, including ceramic armor seats, ceramic components, and ceramic panel systems. In addition, ceramic matrix composites are also used in armored vehicles of the army, such as the Stryker medium armored vehicle.

（8）Used for information technology electronic devices

        There is a strong demand for military ceramic capacitors. Electronic ceramics are widely used in the civilian field. With the acceleration of information technology in weapons and equipment, the demand for electronic ceramics such as ceramic capacitors in the military industry is constantly increasing, especially for multilayer ceramic capacitors (MLCC, with a market share of over 90%). The military market has high requirements for the quality of capacitors, and the size of the Chinese military ceramic capacitor market has maintained a growth rate of over 10% annually.

4.Analysis of Advanced Ceramic R&D and Industrialization Issues

（1）The gap between the domestic advanced ceramic industry and foreign countries

        Currently, there is still a significant gap in the application of advanced ceramic materials in various fields compared to developed countries abroad, especially in terms of basic technology, application technology, and industrialization, which cannot meet the requirements of rapid development of the national economy. There is a certain gap between the domestic advanced ceramic industry and foreign countries, which can be summarized as the following four aspects:

①Market

        At present, the world's most advanced and high value-added advanced ceramic products, especially a large number of ceramic products in high-end equipment, still need to be imported, such as chip piezoelectric ceramic filters used in mobile phones, ceramic insulation bearings for wind turbines, etc. Domestic leading enterprises have a relatively low market share and still have a significant gap with foreign countries.

② Powder and Devices

        At present, there is a significant gap in the purity, dispersibility, uniformity, and performance stability of domestic materials compared to foreign countries, and high-quality powders highly rely on imports; The performance of the device is inferior to that of foreign countries in the 1950s and 1930s.

③ Intellectual Property and Standards

        The layout and standard layout of advanced ceramic intellectual property in China started relatively late, and there is a significant gap in the overall number and quality of patent layouts in intellectual property compared to foreign counterparts. The number and quality of patents applied by leading enterprises are also far from those of foreign counterparts.

④Industrialization capability

        The industrialization timeline, capacity, and output of high-quality advanced ceramics by domestic enterprises are lagging behind those of foreign enterprises.

（2）Reasons for the gap in the domestic advanced ceramic industry

        There are many reasons for these problems in the advanced ceramic industry. We have analyzed the reasons from a holistic perspective, including the following aspects:

① Top level design

        Materials belong to industries rather than industries, and are the foundation and support of various industries. They are related to various industries, and the materials industry has the characteristics of "three highs and three strengths". Therefore, the profits and value of the materials industry are reflected in the extended or related industries. The materials industry places more emphasis on the development of core technologies and platforms, ultimately forming competitive solutions that deepen subsequent applications, rather than simple products or commodities. So there is a special need for top-level design, overall management, strategic layout, and system planning.

② Basic research and applied research

        Due to the system of the school and the mechanism of the enterprise, many directions of basic research in the school are planned in areas with high thesis impact factors and effective graduation for students; The direction of enterprise basic research, due to high investment, long cycle, and slow effectiveness, often places more emphasis on investment that can form short-term benefits through secondary innovation and quickly attract personnel to achieve success. Therefore, the concentration of basic research is high, but the depth, breadth, height, and length are far from enough. Application research actually includes application platforms (research and development to solve the relationship between technology and product efficacy; belonging to the depth of application research) and application centers (research and development to solve the matching degree of technology, products, and commodities; belonging to the breadth of application research). However, due to the insufficient credit foundation between enterprises, it is difficult to establish a moat, and competition and confidentiality have become the main themes. Therefore, application research based on competition and cooperation is difficult to be effective, high-quality, and effective Sustainable progress.

③Mineral resources

        The mineral resources of advanced ceramics in our country, such as zirconium ore and aluminum ore, are poor and there are no large mineral suppliers. The resources heavily rely on imports, and although the processing capacity of minerals is high, deep application is very lacking.

④Talent structure and salary pressure

        When high school students enter university, their enthusiasm for materials science is low, and the proportion of materials and chemistry graduate students is relatively small. In addition, only a small proportion of materials graduate students choose advanced manufacturing industries for employment, resulting in a serious shortage of talent resources. In addition, the salary of graduates in the materials industry is generally lower than that of graduates in industries such as computer science, finance, and the internet, and is lower than the national average salary of graduates. Advanced ceramics are also not popular in the materials field, and people's interest is lower.

⑤ Capital preference

        The investment quantity and amount of external and internal capital in advanced manufacturing industry are significantly lower than those in other industries, while the material industry is even lower.

5.How to seize the commanding heights of high-end manufacturing

        The advanced ceramic system in China is constantly expanding, and the preparation technology is constantly enriching and advancing. The application fields have also been promoted from a single military and aerospace to a wider range of civilian markets such as environmental protection, new energy, and electronic information. Ceramic materials are also developing from structural ceramics and functional ceramics to integrated structure function. In response to the current situation of advanced ceramics in China, key research and development still need to be carried out from several aspects:

        The basic theoretical research and structural design of ceramic technology need to match the development requirements of advanced ceramics in the application field, and provide technical support for new systems, products, applications, and batch transformation.

        The research and industrialization of ceramic powder technology aims to break the current situation where high-end powders are still constrained by foreign countries and meet the basic needs of ceramic material development.

        The research on toughening technology is one of the key to breaking through the limitations of advanced ceramic applications, and toughening technology will achieve revolutionary changes in the application of advanced ceramics.

        Reducing the production cost of advanced ceramics is another key factor in breaking through the limitations of advanced ceramic applications, especially in the development of large-scale production preparation technology, precision manufacturing technology of production equipment, and precision machining technology of ceramics, which will determine the ability to reduce costs.

        Injection molding, coagulation molding, and solid mold free molding technologies will become the most promising batch application molding technologies. Microwave sintering and discharge plasma sintering technologies will bring a qualitative leap to the performance of ceramic materials.

        In accordance with the requirements of the 13th Five Year Plan and industrial development, energy storage ceramics for energy conversion carriers, filtration ceramics (membranes) that play a prominent role in environmental protection, and other functions such as structural integrated ceramics, structural ceramics with excellent comprehensive performance represented by silicon nitride, and optoelectronic ceramics represented by AlON transparent ceramics will become the main force in application and research.

        The development of advanced ceramic materials today is no longer limited to traditional technology, but more is the combination of modern information, automation technology, and different materials to form new technological sciences (computational materials science, functional structural integration, etc.). A new era of advanced ceramic development is about to arrive.