无压浸渗工艺制备Al/SiCp复合材料的研究

摘要

本文利用凝胶注模工艺和无压浸渗技术相结合的方式,首先利用凝胶注模工艺制备碳化硅预制体,然后利用无压浸渗工艺制备颗粒直径为40μm、固含量为55vol%的碳化硅颗粒增强铝基复合材料.对制备出的复合材料抗弯强度和弹性模量进行测试.研究结果表明:铝合金完全渗入到坯体内部,只在铝合金与坯体接触面有剩余铝合金,其他表面均没有多余铝合金液渗透出来;通过光学微观组织观察发现碳化硅颗粒与铝合金基体结合良好、碳化硅颗粒均匀分布在铝合金机体内无明显的偏聚现象.复合材料抗弯强度为242.57MPa,弹性模量为159.62GPa.%In this paper, by combining gelcasting technique with pressureless infiltration technique firstly gelcasting technique was used to prepare SiC preform and then pressureless infiltration technique was used to fabricated particle diameter of 40μm and 55vol%SiC reinforced Al alloy matrix composite. Bending strength and elastic modulus of the composite were tested. The results exhibit that aluminum completely penetrate into the preform, only the aluminum alloy surface that contacts with the preform remaining aluminum, the other surfaces are not permeated out excess liquid aluminum; the SiC reinforced particles and Al alloy matrix combine well, and SiC particles uniformly distribute in the composite without obvious segregation, observed by the optical microstructure. Thecomposite bending strength is 242.57MPa,and elastic modulus is 159.62GPa.