中文摘要：

开发了Al-K2ZrF6体系熔体反应法合成原位铝基复合材料，采用XRD，SEM和TEM分析了复合材料中相组成、微观组织和界面结构。实验结果表明：合成的增强相为Al3Zr颗粒，常规金属型铸造的复合材料中其尺寸在3μm～4μm左右，一般成聚集态分布，颗粒形貌基本为长方体状：该复合材料经重熔快淬成形后，颗粒尺寸减小，基本为粒状，并弥散分布于基体上。Al3Zr／Al复合材料的界面结构研究表明，Al3Zr颗粒与Al存在一定的晶体学位向关系：[^-2^-21]Al3Zr∥[100]Al，（012）Al3Zr∥（1^-10）Al，其点阵错位度仅为10．87％，这表明Al3Zr颗粒可作为基体Al相的形核衬底。Al3Zr／Al复合材料的力学性能测试显示，当Al3Zr颗粒体积分数为11.2％时，抗拉强度和屈服强度分别为148．7MPa和110．2MPa，而且Al3Zr／Al复合材料的抗拉强度和屈服强度均随颗粒体积分数增加显著提高。

英文摘要：

A novel in-situ particulate reinforced aluminum matrix composite has been successfully developed by direct melt reaction （DMR） technique in the Al-K2ZrF6 system. Phase composition, morphology and interface microstructure in the composite were investigated by scanning electron microscope （SEM）, X-ray diffraction （XRD）, and transmission electron microscopy （TEM）. The experimental results indicate that the reinforcement phase synthesized in the Al-K2ZrF6 system is Al3Zr particle. The size of Al3Zr particle is about 3 μm-4 μm. The micro-morphology of Al3Zr particle is mainly in the shape of rectangle under the condition of conventional permanent mould casting. But, after the same composite is re-molten and formed by rapid solidification, the size of Al3Zr is reduced significantly and well-distributed in aluminum matrix in the shape of polyhedron. The interfacial structure of Al3Zr/Al was analyzed by transmission electron microscopy （TEM）. The result shows that there is a crystallographic orientation relationship of [^-2^-21]Al3Zr∥[100]Al and （012）Al3Zr∥（1^-10）Al. Therefore, it may be concluded that the matrix Al phase can nucleate on the substrate Al3Zr particles with a small lattice mismatch 10.87%. The tensile strength and yield strength of Al3Zr/Al composites are σb= 148.7 MPa and σy=110.2 MPa, respectively, when the particle volume fraction is 11.2%. Furthermore, the tensile strength and yield strength of Al3Zr/Al composites are both improved with the increasing of Al3Zr particulate volume fraction.