【作者】 高珊；

【导师】 赵浩峰； 池成忠；

【作者基本信息】 太原理工大学 ， 材料加工工程， 2004， 硕士

【摘要】 本文着重研究了液态浸渗法制备纤维增强镁、铝基复合材料的浸渗工艺。由于纤维与镁、铝合金基体的润湿性差，为了改善纤维与镁、铝合金基体润湿性，我们通过实验，采用洗涤法和热分解法给纤维去胶，然后用溶胶—凝胶法在碳纤维表面覆盖Al₂O₃等薄膜。实验的结果表明：在氮气保护下，碳纤维的高温表面处理效果较好。溶胶—凝胶法涂覆Al₂O₃，使得纤维与镁、铝基体的润湿性有了很大的改善，为纤维增强镁、铝基复合材料的制备开辟了一个新的途径。 本文以镁铝基复合材料的冲击韧性、硬度及抗拉强度为评价指标，对碳纤维增强镁铝基复合材料的主要成分和制备工艺参数进行了正交试验。 本文还在将纤维当作“毛细管束”并假定浸过它的液态金属流为层流的基础上，采用达西定律，对液态金属浸渗动力学进行了理论分析，并推导出了自浸渗（无压浸渗）时液态前沿的最 太原理工大学硕士研究生学位论文小压力计一算公式。结果表明:对非润湿体系，只有克服临界浸渗压力，刁‘能实现纤维的浸渗。临界浸渗压力与金属液体的表面张力、纤维体积分数以及气体的反压力有关。 本文最后研究了纤维增强镁、铝基复合材料试样在3.5%NaCI水溶液、O.O5mol几稀盐酸溶液以及l%NaZCO3水溶液中的腐蚀行为。实验结果表明:镁、铝基复合材料试样在3.5%NaCI水溶液、0.05mof几稀盐酸溶液中的腐蚀性较差，在1%NaZc03水溶液中耐腐蚀性能好，热处理对它们耐腐蚀性的影响是不同的。更多还原

【Abstract】 Infiltration process of fiber reinforced magnesium aluminium matrix composites made by liquid infiltration was mainly studied in the paper. Because the magnesium liquid doesn’t wet the carbon fiber better, in order to improve the wettability, we can adopt heat treatment and washing method taking out the film of the fiber by experiment. And we can obtain the Al2O3 sol-gel, and the sol-gel can coat on carbon fiber. The better result was obtained by the high temperature surface treatment of carbon fiber under the atmosphere of nitrogen. The wettability between fibers and liquid metal was improved by coating Al2O3 sol-gel, and we find a new method to obtain the MMCs.The infiltration kinetics of liquid metal into fibers wastheoretically analyzed and simulated on the basis of Darcy law and the assumptions that the porous fiber was treated as bundles of capillaries and liquid penetrating the fiber was considered to be laminar. The results showed that as for the unwetting system, the liquid infiltration could be possible only when the critical infiltration pressure which was related with the surface tension of liquid metal, fiber volume fraction and the gas counterpressure was reached.In the latter part of this paper, the corrosion behavior of C/Mg composites in the solution of 3.5%NaCl , 0.05mol/L diluted hydrogen chloride and 1% Na2CO3 was studied. The experiment indicated that C/Mg composites had a better erosion resistance in 1% Na2CO3 than in the solution of 3.5%NaCl and in 0.05mol/L diluted hydrogen chloride. There was a difference impact of heat treatment on their corrosion resistance.更多还原