Al_2O_3/ZA12复合材料凝固组织的研究

Study on Solidifying Structures of Al_2O_3/ZA12 Composites

利用挤压铸造制备了Al2O3／ZA12复合材料，研究了其凝固组织．结果表明，复合材料的基体组织细小，合金元素通过适当的化学反应可改善纤维与基体的结合；在凝固过程中，Al2O3纤维可作为ZA12中共晶体非自发形核的衬底，纤维／基体界面上的硅在共晶体的共生生长过程中起了领先相作用，导致复合材料的共晶转变是由铝硅共晶转变和锌铝共品转变组成。

Al2O3/ZA12 composites are manufactured by squeeze casting, and the solidifying structure of the composite are studied. The results indicate that the matrix structures in the composite are very small,and the alloy elements can improve combination between the fiber and the matrix through the suitable chemical reaction;the fiber can serve as the sites of heterogeneous nucleation of eutectic in ZA12 during the solidification of the composite, and the silicon on the interface between the fiber and the matrix plays a leading role during the coupled growth of the eutectic so that the eutectic transformation of the composite consists of aluminum-silicon eutectic transformation and zinc-aluminium eutectic transformation.