Status Quo of Cold Spraying Technology at Home and Abroad

       Russia is the first country to propose the concept of cold spraying, and has carried out related theoretical and experimental research and applied for a patent. They established a two-dimensional gas dynamic model; discussed the process of gas flow, heat and momentum transfer to particles; investigated particle impact and deformation behavior; analyzed the microstructural characteristics of coatings; tried a variety of metal material coatings The preparation of ; related application studies were carried out. At the same time, a variety of low-cost cold spray systems have been developed, such as Rus Sonic, Tev Tech, Dymet, etc.



In the United States, the main research units are Sandia National Laboratory, Pennsylvania University and ASB Industries. The cold spray technology introduced by Papyrin in the early days was mainly researched and developed under the funding of the Consortium of Enterprises (CRADA), with relatively little government funding. Later, ASB Industries organized NASA GRC, Pratt & Whitney and many aerospace companies to conduct applied research in the aerospace field.



At present, ASB Industries has successfully promoted cold spray technology to practical engineering applications, and there are several practical applications in the aerospace industry alone, and most of them are patented. In addition, the American Society for Materials Professional Committee on Thermal Spraying (ASMTSS) also successfully held 3 special conferences on cold spraying. Inovati Corporation of the United States has also launched the KINETIC METALLIZATION system (KMCDS series), the main feature of which is to use low pressure (<1MPa) He to achieve metal ceramic (such as WC-Co) coating through a specially designed straight-through nozzle. preparation.



Dr. Christian Moreau of the National Research Council of Canada (NRC) has incorporated cold spray technology into thermal spray equipment, conducting some characteristic experiments while forming an industrial collaborative team to develop its application in aerospace. Roman Maev of the University of Windsor independently developed a low-cost cold spray system, which is more suitable for the preparation of MMC (Metalle Matrix Composite, metal matrix composite) coatings. Daimler Chrysler will focus its research on the development of anti-corrosion coatings for automobiles. At present, there are some devices that have been commercialized.



There are many research institutions in Germany engaged in cold spray research, including the Federal Armed University of Germany, the University of Hamburg, the European Institute of Aeronautics and Astronautics (EADS), Ottobrunn (in cooperation with RWTH Aachen University), Linde, and Munich CGT (ColdGas Technology). Germany's Federal Armed Forces University and the University of Hamburg formed a team of more than a dozen scientists to conduct research on all aspects of cold spray technology, including theory, modeling, design and development of nozzles, coating preparation and characterization, and development of coating applications, etc. . In addition, the German Federal Armed University cooperated with Linde Gas and other companies to set up Cold Gas Technology (CGT) to sell commercial cold spray systems. Such as the early development of the Kinetic-3000 computer-controlled cold spray system, which has been recognized internationally. Since then, CGT has launched an improved Kinetic-4000 cold spraying system. On the one hand, the system can realize the preheating of the powder feeding gas, improve the temperature and deformation ability of the particles, thereby further improving the coating quality and production efficiency; In this aspect, the coating preparation of difficult-to-spray materials, such as cermets, can be realized.



The French Atomic Energy Commission and the Paris Mining University are engaged in research on cold spraying with government funding, and are equipped with CGT's cold spraying systems to meet commercial production needs. In 2006, a Cold Spray Club (Cold Spray Club) was established at the Paris Mines University, holding seminars every year to exchange research and application progress of cold spray technology. The inner hole cold spray system developed by the French Lermps laboratory based on the optimized design of the nozzle can also produce high-quality coatings.



Yazaki Auto Parts Company of the United Kingdom is one of the first units in the world to start the research and development of cold spray applications. They have developed the application of copper wire harnesses in automotive electronics; the University of Nottingham has a large-scale cold spray project; Oxygen and Cambridge University cooperate in research Recycling of helium, a cold spray system has been designed and built at the University of Cambridge. The William 0'Neil research group has received substantial funding to investigate the application of cold spray in near-net shape and tool making.



In Asia and the Pacific, Australia's Science Council and Industrial Research Organisation (CSIRO) has established a well-equipped cold spray laboratory and provides Australian businesses with cutting-edge applications of this technology. The team was established in 2003 and is technically led by Dr. Mahnaz Jahedi. It is equipped with a Kinetic-3000 cold spray system from CGT, Germany.



South Korea has also established a national laboratory for cold spray with government funding. South Korea's Taekwang Technology Co., Ltd. has introduced the DPD-2004 computer-controlled cold spray system by improving the Kinetic-3000 system. The system adds a heater for feeding powder gas, thereby realizing the preparation of coatings for difficult-to-spray materials (such as WC-Co). At present, there have been many reports on the preparation of amorphous alloy coatings by cold spraying at Hanyang University.



In Japan, Shinshu University was the first to carry out research on cold spray technology, and the related work included both theory and experiment; then, the National Institute of Materials Science and other units also joined the research team; in 2004, a university and research institute was established. The associations composed of , industrial sectors are dedicated to the research and development of cold spray technology; some companies such as Toyota Automobile and Nippon Steel have negotiated to equip cold spray equipment for industrial application, and currently cold spray high-performance conductive coatings have been applied to the electronics industry.



In recent years, some domestic universities and scientific research institutions have also carried out in-depth research on cold spray technology, and have achieved certain results. The earliest institutions engaged in cold spray technology research in China mainly include Xi'an Jiaotong University, Institute of Metal Research, Chinese Academy of Sciences, and Dalian University of Technology. Some other institutions have also begun to engage in the research and development of cold spray technology, such as Baoshan Iron and Steel Co., Ltd. Technology Center Frontier Technology Research Institute, Harbin Welding Research Institute, No. 725 (Qingdao), Beijing University of Science and Technology, Shenyang University of Technology, Chongqing University, Ocean University of China, etc. The research content covers airflow simulation, process and equipment optimization, bonding mechanism, development of new coating materials, and expansion of application fields.