摘要
采用A356-(K2ZrF6+KBF4+Na2B4O7)作为熔体直接反应体系制备(ZrB2+Al2O3+Al3Zr)/A356复合材料。利用XRD、SEM和TEM等测试技术研究复合材料的相组成和微观组织。结果表明,复合材料增强相由ZrB2和Al2O3陶瓷相颗粒和Al3Zr金属间化合物相颗粒组成。ZrB2颗粒易团聚形成颗粒团簇并沿α(Al)合金晶界分布;ZrB2颗粒的微观形貌为六边形,尺寸在50nm左右。TEM研究发现,Al3Zr颗粒以小面形式生长,其长径比约为20;Al2O3颗粒形貌为长方体状和椭圆状,尺寸约为0.1μm。此外,基体与颗粒的相界面干净,无界面反应物生成。
（ZrB2＋Al2O3＋Al3Zr）/A356 composites were synthesized by melt direct reaction from A356-（K2ZrF6＋KBF4＋Na2B4O7） system.The phase compositions and the microstructures of the as-prepared composites were investigated by XRD,SEM and TEM.The results show that the reinforcements are composed of ZrB2 and Al2O3 ceramic phase particles and Al3Zr intermetallic particles.The ZrB2 particulates are easy to join together to form some particle clusters and distribute along the α（Al） grain boundary.The morphologies of the ZrB2 particulates are in hexagon-shape with the size of about 50 nm.The TEM investigation results of Al3Zr indicate that Al3Zr grows in the form of facet with the length-diameter ratio of about 20.The morphologies of Al2O3 particles are in rectangular-shape and ellipsoidal-shape,with the size of about 0.1 μm.In addition,the interfaces of the matrix and particles are net and no interfacial outgrowth is observed.
基金
Project(50971066) supported by the National Natural Science Foundation of China
Project(20070299004) supported by Research Fund for the Doctoral Program of Higher Education of China
Project(2008-46) supported by Jiangsu Provincial '333' Project of training the High-level Talents Foundation,China
Project(BE2009127) supported by Jiangsu Provincial Science Supporting Item,China
关键词
铝基复合材料
熔体直接反应
原位颗粒
微观组织
aluminum matrix composites
melt direct reaction
in situ particle
microstructure
