Application of the hottest nano coating powder mat

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Application of nano coating powder material in "2 machine, 3D" industry

in the industrial field, coating powder material is a surface engineering application material, which is coated on the surface of the substrate to play a role of wear resistance, corrosion resistance, high temperature resistance, oxidation resistance, aging resistance, and meet the special functions or functions of light, electricity, magnetism and so on. With the manufacturing of some products becoming more and more sophisticated and the service conditions becoming more and more stringent, the requirements for surface coating materials are also higher. It is found that when the characteristic scale of materials is reduced to the nano scale, the properties of materials will be significantly different from those in the macro world due to small-scale effect, quantum effect, interface or surface effect, etc. This has also prompted the idea of scientists to integrate nanotechnology with surface engineering

surface engineering is a special field, which is an industry combining materials and processes. There are only materials, and the coating process is bad or uneconomical, which cannot be carried out. Thermal spraying is a relatively mature technology, which is the most popular and cost-effective. How to use thermal spraying technology to spray nano materials has been a difficult problem for people to consider. Because nanoparticles are tiny particles, if thermal spraying is used, nanoparticles will be ablated or blown away instantly, and the material cannot reach the matrix, let alone form an effective functional coating. The solution is not to give oil or eliminate the agglomeration of nanoparticles to form micron sized particles. In this way, not only the special effect of nano materials, but also the thermal spraying process can be implemented. To this end, scientists in the United States began to conduct research in the 1990s. Fortunately, Chinese scientists later joined the research team, and finally succeeded in the hands of Professor Wang Yu, a pioneer in the field of nano material spraying and an internationally renowned scholar. In 2000, the first product, nano aluminum titanium powder coating powder material, was industrialized in the United States nano materials company. Its compactness reached 95% - 98%, the bonding strength increased by 2-3 times year-on-year, and the wear resistance increased by 3-8 times. Now the products of this company are specially supplied to the United States Navy. At present, this nano agglomeration technology has matured, and more product series can be developed through this technology

nano coating has a wide range of applications, especially in the application of aero-engine and gas turbine (2) hot end components, which is of greater significance. Because the 2-machine equipment is not only an important symbol of national science and technology, industry and economy, known as the treasure of the country and the "pearl on the crown" of modern industry, but also plays an important strategic role in our national defense construction. It needs to equip the blue sky with China's own heart, which is the highest national will of China's manufacturing industry

however, the heart disease of aero-engine has been plaguing China's aviation industry. Experts predict that in the next 10 years, China's air force and Navy will add about 3000 military aircraft, with a corresponding engine demand of more than 6000. The whole market scale of cast iron sample machine for military and civil aviation engines exceeds trillion yuan. Therefore, our country has a more urgent demand for 2-machine equipment and its key materials, including coating materials. In November, 2014, the National Natural Science Foundation of China held the Shuangqing forum with the theme of "challenging scientific issues in the technology and application of thermal barrier coatings for Aeroengines". Experts pointed out that thermal barrier coating technology is one of the key technologies in the aviation propulsion plans of countries all over the world, and has great application prospects. The United States, Britain, France, Russia and other world aero-engine powers have widely applied thermal barrier coating technology in the fields of aviation and aerospace, and further extended it to industrial fields such as electric power and energy. At the same time, this technology has been listed as the core top secret technology and blocked. For this reason, the 2 machine has been included in the national major science and technology projects and has become a national strategy. In March 2016, the National People's congress reviewed and approved the "13th five year plan" of 100 major engineering projects to be launched in China, with 2 units ranking first

for high-performance aeroengines, the most difficult part of their development lies in materials and manufacturing processes, because performance requirements beyond the limit must ultimately be implemented in the development of cutting-edge materials and manufacturing processes. Experts pointed out that the difficulties and performance gaps in the development of aeroengines in China are mainly reflected in the materials and processes of turbine blades and turbine disks. The most basic requirement of modern aviation turbine engine for turbine performance is to work reliably and stably under high temperature, high pressure and high speed conditions. Among them, high-performance blades integrate advanced materials, advanced molding technology, advanced cooling technology and advanced coating

at present, the service life of thermal barrier coating of aviation engines in China, especially military engines, is only 100 hours, while that of Russian products can reach more than 1000 hours, and that of American products can reach more than 3000 hours, with a significant gap. At the same time, with the increase of the thrust weight ratio of the engine, the temperatures of the combustion chamber, turbine and compressor are also rising significantly, especially the turbine inlet temperature is increasing at the rate of almost 15 ℃ every year. Even if advanced directional solidification superalloy and single crystal superalloy are used as turbine blades, supplemented by advanced cooling technology, they cannot meet the requirements of heat insulation, corrosion resistance and oxidation resistance. Therefore, high temperature protective coating materials are developing in the direction of long life, low thermal conductivity and good thermal radiation shielding. Its R & D and localization have become a top priority of China's aviation industry

thermal barrier coating (TBC) is mainly used on aircraft engines, turbines and turbine blades to protect the superalloy matrix from high-temperature oxidation and corrosion, and plays the role of heat insulation, increasing engine inlet temperature and increasing engine thrust weight ratio. The 7 ± 1wt%y2o3 stabilized ZrO2 (i.e. 8YSZ) material system has been used for decades, and its service temperature is below 1200 ℃. With the improvement of engine and turbine performance, especially the service temperature of military aircraft engine blades has exceeded 1200 ℃, the original material is no longer suitable, and the development of new coating materials has become an urgent need in the military industry. In 2014, the Ministry of industry and information technology released the special key direction of industrial strength base. Among the seven coating materials listed in the direction of high-performance coating materials for surface strengthening of industrial parts to improve the basic capacity of high-end equipment, two are related to thermal barrier coating materials. One is multi-component MCrAlY material as the bonding layer of thermal barrier coating, which requires its bonding strength ≥ 50MPa, 1050 ℃ water quenching ≥ 50 times, 1050 ℃ (200H) complete oxidation resistance; One is the multiphase ceramic material as the surface layer of the thermal barrier coating, which is required to have no phase transition at 1200 ℃ (100h) and a thermal conductivity of 1.2w/m · K. In short, the thermal barrier coating is required to have a bonding strength of more than 50MPa and can be used for a long time at a working temperature of more than 1200 ℃

The same is true for gas turbines. At present, domestic enterprises have not mastered the core technology, and multinational companies have mastered the gas turbine supply and maintenance market. The result of monopoly is to pay a high price, which is not only reflected in the initial investment, but also the operation and maintenance cost is surprisingly high. Take Shanghai Caojing natural gas power plant as an example. Since its completion, a staggering 383million yuan has been spent on overhaul and maintenance between 2009 and 2011, which has exceeded 13% of the total investment. The cost of Shanghai Lingang gas turbine is even more amazing. Siemens' long-term maintenance costs an average of 120million yuan a year. In these maintenance projects, the coating of hot channel components generally falls off, cracks and burns, which account for 80% of the total maintenance cost

aiming at the major national needs, the research group of Professor Wang Yu from the Nano Surface Engineering Laboratory of Harbin Institute of technology has made great efforts in the research of thermal barrier coatings and transition alloy layers. They have created several unique alloy and ceramic powder materials with precise composition control, high density, good sphericity, narrow particle size distribution range and good fluidity, which can not only be widely used to prepare the key core parts of the 2 machine, but also be expected to be used for 3D printing parts

through special nano powder granulation control technology, they developed nanostructured zirconate thermal barrier coating powder materials, breaking through the current limit that China's aircraft engine thermal barrier coating materials can not be used at temperatures above 1200 ℃, and providing technical support for China's development of high-end engines. The thermal insulation effect of the nanostructured double ceramic coating prepared with this zirconate powder material is more than 70% higher than that of the traditional micro structure single ceramic layer 8YSZ thermal barrier coating with the same thickness, which is now widely used. In addition, the double ceramic coating with the correct hardware and software setting structure of the nano junction has better thermal shock performance

multi component MCrAlY (m=ni/co/ni+co) series superalloy powder materials are widely used as the bonding layer of thermal barrier coatings, or as a separate coating on aircraft engines and gas engines, because they have the advantages of good high-temperature oxidation resistance and thermal corrosion resistance, good plasticity, similar thermal expansion coefficient to the matrix, little impact on the matrix performance, adjustable composition, etc, It can also be directly used as a high-temperature protective coating against high-temperature oxidation, vulcanization corrosion and erosion at 800 ℃ - 1100 ℃. Therefore, MCrAlY alloy powder is an important material widely used for high temperature protective coating of hot end components such as engine and turbine blades. Due to the development of 3D printing technology, this MCrAlY alloy powder is expected to be directly used to print hot end components such as engine and turbine blades, so as to change the multiple processes of re spraying thermal barrier coating on the superalloy substrate before the target is relatively large, and directly and quickly 3D print out blades and other components with the function integration of substrate and coating material

the modified MCrAlY series superalloy powder developed by the Nano Surface Engineering Laboratory of Harbin Institute of technology can significantly improve the strength, hardness, thermal shock resistance, high-temperature oxidation, vulcanization and corrosion resistance of final parts, and the bonding strength between the coating and the substrate can reach more than 60MPa when used as a coating, It is far higher than the requirement of bonding strength ≥ 50MPa in the special key direction of the Ministry of industry and information technology in 2014

additive manufacturing (3D printing) is known as the third industrial revolution and has developed rapidly in recent years. However, the development of 3D printing in China is facing a serious bottleneck, that is, consumables. Lu Bingheng, an academician of the Chinese Academy of engineering, clearly pointed out that the prospect of additive manufacturing is "creating materials". The development of new materials with ultra-high strength, ultra-high temperature resistance, ultra-high toughness, ultra-high corrosion resistance and certain environmental adaptability may become a breakthrough in China's 3D printing market. Moreover, the profitability of 3D printing materials is the strongest in the industrial chain. The gross profit margin of 3D printing materials is 60% - 80%, much higher than that of other links of 3D printing

to sum up, nano coating powder materials have great application potential in improving China's equipment manufacturing. Therefore, the research team has established Beijing Chuntian Nano Technology Co., Ltd. and hopes to apply these products to China's aero-engine and gas turbine equipment in the near future and contribute to our country's national defense

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