Al-Ti-B-RE中间合金第二相的形态及分布对工业纯铝细化效果的影响

Effect of the Morphology and Distribution of the Second Phases of Al-Ti-B-RE Master Alloys on Refining Commercially Pure Aluminum

摘要:

为更好地优化组织，提升细化性能，采用熔配—纯金属钛法制备新型铝晶粒细化剂—铝钛硼稀土Al-Ti-B-RE中间合金。试验结果表明：合成反应温度不同，所制备的Al-Ti-B-RE中间合金第二相所具有的形态分布及数量不同，低温反应合成中间合金第二相Al3Ti和Ti2A120RE稀土相为小块状，高温度反应合成则为长片状。借助X射线衍射（XRD）、扫描电镜（SEM）、光学显微镜（OM）等技术对其第二相的微观形貌分布、细化效果及形核能力等进行表征分析。结果表明：第二相粒子形态分布及数量对细化效果有重要影响，第二相中的形核相与基底的错配度越小，越有利于非均质形核，细化效果越好

Abstract:

To obtain better microstructures and improve refining performance, a new aluminum grain refiner Al-Ti-B-RE master alloy was prepared by a mix molten-pure titanium method. The results show that there are small blocks of Al3Ti and Ti2A120RE phases in the Al-Ti-B-RE master alloys prepared at optimal temperatures while there are large flakes at high temperature. The morphology, distribution and quantity of second phases of Al-Ti-B-RE master alloys and refining effects and nucleating potentials were studied by XRD, SEM and OM. It is indicated that the morphology, distribution and quantity of second phase particles of Al-Ti-B-RE master alloys have an important influence on the refining effects. A better refining effect could be obtained with the smaller disregistry between nucleation and the substrate in favor of promoting nucleation