Al-1.0%Sc-1.0%Zr (mass fraction) master alloy was prepared at different cooling rates. The morphology and thermodynamics data of the primary particles of the master alloy were investigated by X-ray diffraction (XRD...Al-1.0%Sc-1.0%Zr (mass fraction) master alloy was prepared at different cooling rates. The morphology and thermodynamics data of the primary particles of the master alloy were investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM) and differential scanning calorimetry (DSC). It shows that the primary particles are dendrite-shaped particles comprised of several attached small cubic, cusped-cubic or crucifer shape particles at slow cooling rate. However, the primary particles are separated with crucifer shape at intermediate cooling rate, and they are cubic with cusped-cubic shape at high cooling rate. Meanwhile, the separated and attached particles present AlaSc/AlaZr1-xScx core-shell structure. The formation mechanism of the structure was systematically investigated by a mathematical model.展开更多
基金Project(2012CB619503)supported by the National Basic Research Program of ChinaProject(2013AA031001)supported by the National High-tech Research and Development Program of ChinaProject(2012DFA50630)supported by the International Science and Technology Cooperation Program of China
文摘Al-1.0%Sc-1.0%Zr (mass fraction) master alloy was prepared at different cooling rates. The morphology and thermodynamics data of the primary particles of the master alloy were investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM) and differential scanning calorimetry (DSC). It shows that the primary particles are dendrite-shaped particles comprised of several attached small cubic, cusped-cubic or crucifer shape particles at slow cooling rate. However, the primary particles are separated with crucifer shape at intermediate cooling rate, and they are cubic with cusped-cubic shape at high cooling rate. Meanwhile, the separated and attached particles present AlaSc/AlaZr1-xScx core-shell structure. The formation mechanism of the structure was systematically investigated by a mathematical model.