铸造ZL101A/SiC_P复合材料的研究  

Study on Castable ZL101A/SiC_P Composites

作　　者：桂满昌[1] 吴洁君[1] 王殿斌[1] 陈彩中[2] 

机构地区：[1]北京航空材料研究院,北京100095 [2]南昌航空工业学院,江西南昌330034

出　　处：《铸造》2001年第6期332-336,共5页Foundry

基　　金：国家"8 63"高技术新材料领域资助项目 (71 5 0 0 5 0 0 70 )

摘　　要：采用真空搅拌复合工艺制备了铸造ZL10 1A/SiC复合材料 ,研究了变质和细化处理对复合材料组织的影响。结果表明 :变质和细化处理是铸造ZL10 1A/SiC复合材料制备工艺的重要处理措施 ,可明显改善复合材料的组织。利用透射电镜对Al/SiC界面特征及界面反应进行分析 ,同时对该复合材料的铸造性能 (熔体合金流动性能、线收缩、体收缩和热裂倾向 )以及力学和物理性能进行了测试。The cast ZL101A/SiC p composites are produced by using stirring-cast method in vacuum condition. The influences of modification by Sr and refinement by Ti and B on microstructure of the composites and the un-reinforced matrix alloy are studied. As has been found in conventional Al-Si alloys, the modification can change the morphology of eutectic silicon phase in the matrix alloy from plate into fiber, and the refinement reduces the grain size of primary aluminum obviously, thus being beneficial to improve the mechanical properties of the composite. The Al/SiC p interfacial characteristics and reaction in the composites are observed by using transmitted electron microscopy (TEM). Most Al/SiC p interfaces are clean. A reaction product of MgAl 2O 4 has been found at some Al/SiC p interfaces and the process of interfacial reaction has been analyzed. The castabilities including the fluidity, contraction and thermal crack of three composites with 10, 15 and 20 vol.% SiC p particles are measured in the condition of sand mold casting. The SiC p particles in the composite decrease the fluidity significantly, and the fluidity decreases with increasing SiC p volume fraction. Therefore the filling ability of the composite melts is inferior to that of the un-reinforced matrix alloy. The addition of SiC p particles decreases the bulk and linear contractions of the composite during solidification and cooling process. To be similar to the un-reinforced matrix alloy, ZL101A/SiC P composites display a quite low thermal crack tendency. The presence of SiC p particles makes the mechanical properties of the composites improved significantly, especially in yield strength and stiffness. The ZL101A/SiC P composites have a low coefficient of thermal expansion and a good thermal conductivity as compared with the un-reinforced matrix alloy.

关 键 词：铸造 复合材料 颗粒增强 铸造性能 力学性能 碳化硅 界面 

分 类 号：TG249[金属学及工艺—铸造]