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Tham khảo tài liệu 'silicon carbide materials processing and applications in electronic devices part 5', kỹ thuật - công nghệ, cơ khí - chế tạo máy phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | 130 Silicon Carbide - Materials Processing and Applications in Electronic Devices of diamond particles. The reason behind this is that the thermal conductivity of the nominally pure aluminium matrix is influenced by take-up of some silicon from the silicon carbide. It was shown in Molina et al. 2008b that the intrinsic value of the thermal conductivity of pure aluminium in composites fabricated via gas-pressure infiltration might be as low as 185 W mK because of the presence of silicon in solid solution in combination with precipitated silicon phase in the matrix. Reactivity of liquid aluminium and SiC in the as-received condition seems unavoidable in gas-pressure infiltration since the time elapsed during pressurization of the chamber and posterior solidification is of the order of some minutes depending on the special characteristics of the equipment at hand. Decreasing as much as possible the infiltration temperature seems then to be a successful way to avoid metal-ceramic reactivity in SiC-based systems. 4.3.2 Metal SiC-graphite flakes composites A very recent family of composite materials has been developed and patented at the University of Alicante Narciso et al. 2007 Prieto et al. 2008 . The invention is concerned with a composite material with high thermal performance and low cost which has a layered structure achieved by proper combination of different components. The components of the material are three 1 a phase mainly formed by graphite flakes phase A 2 a second phase phase B involving particles or fibers of a material which can act as a phase separator of phase A phase B is a ceramic material preferably selected from the group of SiC BN AlN TiB2 diamond and carbon fibers and finally 3 a third phase phase C formed by a metallic alloy. The three present phases must have good thermal properties although their main function is different for each one phase A graphite flakes is the principal responsible of the properties of the final material phase B acts as
