New progress has been made in the study of three dimensional continuous network diamond reinforced aluminum matrix composites
Key words diamond, south central university, composite material | 2020-05-15 10:21:03 | source China superhard material network
With the development of information technology and the advent of 5G era, the pace of Internet of all things is accelerating, and electronic products are gradually developing towards the direction of intelligence, multi-function and light weight.In the process of increasingly powerful performance of electronic products, integrated circuit chips and electronic components are shrinking in size...
With the development of information technology and the advent of the era of 5G, the pace of the Internet of everything is accelerating, and electronic products are gradually developing towards the direction of intelligence, multi-function and lightness.
In the process of increasingly powerful performance of electronic products, the volume of integrated circuit chips and electronic components is constantly shrinking. The continuous improvement of high-density integrated assembly technology leads to a sharp increase in power consumption and heat emission. Therefore, heat dissipation has become a key bottleneck restricting the development of related industries.Among thermal management materials, diamond/metal matrix composites have attracted wide attention due to their excellent thermal conductivity and low thermal expansion coefficient.
At present, the main research ideas at home and abroad are to increase the content of diamond particles and improve the composite interface between diamond particles and metal, both of which have achieved good results.However, diamond particles (thermal conductivity ~2200W/mK) in this composite structure are like thermal islands connected by metals (Al~237W/mK, Cu~398W/mK), which not only increase the number of two-phase interfaces, but also make it difficult to produce synergistic effects, making it difficult to give full play to the excellent thermal conductivity of diamond.
The diamond team of central south university has been committed to building a continuous diamond network skeleton in the composite material, turning the island of high thermal conductivity into a channel of high thermal conductivity.Specific research idea is: with foam metal as the substrate, using chemical vapor deposition technique was used to prepare high quality diamond frame, three-dimensional continuous network recycle gas pressure welding technology and metal composite, the diamond and metal forming interpenetrating network structure, study its macro to micro structure and the mechanism of the interface performance of thermal conductivity of the composites, reveal that the diamond formation of continuous thermal channel, the influence mechanism in the composite material thermal efficiency, with high thermal conductivity of diamond/metal matrix composites provide theoretical and experimental basis for the design and preparation.
In recent years, the diamond team of central south university has been committed to successfully preparing high-quality three-dimensional continuous network diamond by optimizing the temperature field and atmosphere field in the process of chemical vapor deposition. A series of studies have been carried out on its applications in the fields of advanced thermal management materials, organic wastewater treatment and biosensor. Applied Catalysis B:International journals such as Environmental 245 (2019) 420-427, Applied Energy 233-234 (2019) 208-219 (ESI highly cited papers), Materials & Design 156 (2018) 32-41 have published relevant research progress.
"New type of high thermal conductive composite phase change materials, high performance electronic temperature control of the world's leading" in the fifth China "Internet +" won the "gold medal" contest of college students' innovative undertaking, and high score of the creative group leader track number one in the country, the competition by the Ministry of Education, the National Development and Reform Commission, ministry of 12 the central ministries and commissions such as unit and zhejiang province people's government hosted, from 124 countries and regions on five continents, 4.57 million college students, 1.09 million teams compete, entries and the number of students close to the sum of the four series).
The diamond team of central south university recently combined the three-dimensional continuous network diamond with the metal aluminum through the gas pressure fusion technology, and constructed the three-dimensional continuous network diamond fast heat conduction channel in the aluminum matrix.When the volume fraction of diamond is only 4.6 vol.%, the heat conduction rate of the composite material during heating and cooling is significantly higher than that of pure aluminum and pure copper.The thermal conductivity of the composite material is 315.7w /mK, which is 54% higher than that of pure aluminum. However, the contribution value (thermal conductivity efficiency) of the diamond reinforcement per unit volume fraction to the thermal conductivity of the composite material is much higher than that of the aluminum matrix composite reinforced by traditional particle configuration diamond.
The research results, entitled "Construction of 3D interconnected diamond networks in al-matrix composite for high-efficiency thermal management", were published in the international authoritative Journal Chemical Engineering Journal 380 (2020) 122551.Zhang long, a doctoral candidate of central south university in 2016, was the first author, while associate professor wei qiuping, associate researcher ma li and professor zhou kechao were the co-corresponding authors.The research work was supported by the state key research and development program, the national natural science foundation of China and the state key laboratory of powder metallurgy.
Diamond besides as a diamond is a precious of aesthetic value, but also has a series of excellent physical and chemical properties, including the highest hardness and elastic modulus, high breakdown voltage, thermal conductivity, carrier mobility, very low linear expansion coefficient, friction coefficient, wide band gap, optical transmittance, good chemical stability and biocompatibility, pure diamond for good insulation, can become good after doping semiconductor may even become superconductors, etc., these excellent performance integration makes diamond in nature the most solid technology and artistic value.
Chemical vapor deposition (CVD) synthesis in recent 40 years was a huge breakthrough, make the CVD diamond in the not too distant future, marketization, industrialization, scale, at the same time, engineers and designers all over the world are actively exploring and mining potential application value of CVD diamond, and it has been in the medical diagnosis, electrochemical sensor, water treatment, radiation detection, high power devices, acoustic devices, magnetic measurement and new type of laser, and many other fields has made good progress.
The research work of the diamond team of central south university in the field of three-dimensional continuous network diamond will provide new ideas for the application of diamond in the fields of electronic packaging thermal management, electrochemical oxidation, electrochemical synthesis and electrochemical analysis.
The thesis links: http://libdb.csu.edu.cn/rwt/SCI/https/P75YPLUUMNVXK5UDMWTGT6UFMN4C6Z5QNF/science/article/pii/S1385894719319540?Via % 3 dihub