Effect of chromium carbide coating on thermal properties of short graphite fiber/Al composites
Effect of chromium carbide coating on thermal properties of short graphite fiber/Al composites
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DOI：
10.1007/s10853-014-8272-6
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发表时间：
2014-06
影响因子：
4.5
通讯作者：
Tingting Liu;Xin-Bo He;Qian Liu;S. Ren;Qiping Kang;Lin Zhang;X. Qu
中科院分区：
文献类型：
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作者：
Tingting Liu;Xin-Bo He;Qian Liu;S. Ren;Qiping Kang;Lin Zhang;X. Qu
采用熔盐法在石墨纤维表面制备碳化铬涂层，以改善真空压力浸渗法制备的石墨短纤维/铝复合材料的界面结合性能和热性能。通过改变电镀时间，制备了不同碳化铬涂层厚度的石墨纤维/铝复合材料，研究了碳化铬涂层对复合材料组织和热性能的影响。采用Maxwell-Garnett有效介质法和声学失配模型相结合的方法对复合材料的导热系数进行了理论预测。结果表明，熔盐条件下在石墨纤维表面形成的碳化铬涂层主要由Cr7C3相组成。结果表明，镀膜时间为60min、厚度为0.5gμm的Cr7C3涂层对改善石墨纤维与铝基体的界面结合、降低界面热阻效果最好。厚度为0.5μm的40%Cr7C3涂层石墨纤维/铝复合材料的面内导热系数为221W/m−1K−1比未涂层复合材料的面内导热系数提高了45.4%，热膨胀系数为9.4W×10−6K−1，是一种非常有意义的热管理应用材料。
A chromium carbide coating was synthesized onto graphite fibers by molten salts method to improve the interfacial bonding and thermal properties of short graphite fiber/Al composites which were fabricated by vacuum pressure infiltration technique. The graphite fiber/Al composites with different thicknesses of chromium carbide coatings were prepared through varying plating times to investigate the influence of chromium carbide layer on the microstructures and thermal properties of the composites. The combined Maxwell–Garnett effective medium approach and acoustic mismatch model schemes were used to theoretically predict thermal conductivities of the composites. The results indicated that the chromium carbide coating formed on graphite fiber surface in molten salts consists mainly of the Cr7C3phase. The Cr7C3-coating layer with plating time of 60 min and thickness of 0.5 μm was found to be most effective in improving the interfacial bonding and decreasing the interfacial thermal resistance between graphite fiber and aluminum matrix. The 40 vol% Cr7C3-coated graphite fiber/Al composite with Cr7C3thickness of 0.5 μm exhibited 45.4 % enhancement in in-plane thermal conductivity of 221 W m−1K−1compared to that of uncoated composite, as well as the coefficient of thermal expansion of 9.4 × 10−6K−1, which made it as very interesting material for thermal management applications.