Near-net shaped Al/SiCP composites via vacuum-pressure infiltration combined with gelcasting  

凝胶注模与真空压力浸渗法近净成形制备Al/SiC_P复合材料

作　　者：Cui-ge DONG Ri-chu WANG Yi-xin CHEN Xiao-feng WANG Chao-qun PENG Jing ZENG 董翠鸽;王日初;陈以心;王小锋;彭超群;曾婧(中南大学材料科学与工程学院,长沙410083;湖南省电子封装与先进功能材料重点实验室,长沙410083)

机构地区：[1]School of Materials Science and Engineering,Central South University,Changsha 410083,China [2]Hunan Provincial Key Laboratory of Electronic Packaging and Advanced Functional Materials,Changsha 410083,China

出　　处：《Transactions of Nonferrous Metals Society of China》2020年第6期1452-1462,共11页中国有色金属学报（英文版）

基　　金：Project (CXZZ20140506150310438) supported by the Science and Technology Program of Shenzhen City, China;Project (2017GK2261) supported by the Science and Technology Program of Hunan Province, China;Project (2017zzts111) supported by the Fundamental Research Funds for the Central Universities, China。

摘　　要：To solve the problem of difficult machining, the near-net shaped Al/SiCP composites with high volume fraction of SiC particles were fabricated by vacuum-pressure infiltration. The SiCP preform with a complex shape was prepared by gelcasting. Pure Al, Al4Mg, and Al4Mg2Si were used as the matrices, respectively. The results indicate that the optimal parameters of SiCP suspension in gelcasting process are pH value of 10, TMAH content of 0.5 wt.%, and solid loading of 52 vol.%. The Al matrix alloyed with Mg contributes to improving the interfacial wettability of the matrix and SiC particles, which increases the relative density of the composite. The Al matrix alloyed with Si is beneficial to inhibiting the formation of the detrimental Al4C3 phases. The Al4Mg2Si/SiCP composite exhibits high relative density of 99.2%, good thermal conductivity of 150 W·m^-1·K^-1, low coefficient of thermal expansion of 10.1×10^-6 K^-1, and excellent bending strength of 489 MPa.针对Al/SiCP复合材料机加工困难的问题,首先采用凝胶注模法得到具有复杂形状的SiCP预制块,再通过真空压力浸渗近净成形制备具有高SiCP体积分数的Al/SiCP复合材料。复合材料基体采用三种合金,分别为纯Al、Al4Mg和Al4Mg2Si。结果表明:适用于凝胶注模的SiCP浆料最佳参数为pH 10,TMAH含量0.5%(质量分数)和固相体积分数52%。在Al基体中添加Mg能改善基体与SiCP颗粒界面的润湿性,从而提高复合材料的相对密度;在Al基体中添加Si有助于抑制有害界面相Al4C3的生成。制备的Al4Mg2Si/SiCP复合材料具有较高的相对密度(99.2%)、良好的热导率(150 W·m-1·K-1)、较低的线膨胀系数(10.1×10-6 K-1)以及优异的弯曲强度(489 MPa)。

关 键 词：Al/SiCP composites GELCASTING vacuum-pressure infiltration microstructure properties 

分 类 号：TB333[一般工业技术—材料科学与工程]