摘要
In order to investigate the existing form and action mechanism of minor scandium (Sc) and zirconium (Zr) in Al-Cu-Mg alloy, microstructures of Al-4Cu-1Mg-Sc-Zr alloy under different conditions, including states of as-cast, homogenized, hot-rolled, as-solution and natural aged, were observed by scanning electron microscopy (SEM), X-ray diffractometry (XRD) and transmission electron microscopy (TEM). It is revealed that Sc and Zr are completely dissolved into the supersaturated solid solution in as-cast ingot, but grain refinement is not observed. Coffee-bean-like Al3(Sc, Zr) particles deposit during homogenization of ingot induce an increase in hardness. Al3(Sc, Zr) particles are slightly coarsened in as-solution samples, but they still maintain coherent to matrix, which indicates a high thermal stability of these particles. Good coherency of Al3(Sc, Zr) particles makes some benefits for inhibiting recrystallization and reserving work-hardening.
In order to investigate the existing form and action mechanism of minor scandium (Sc) and zirconium (Zr) in AI-Cu-Mg alloy, microstructures of Al-4Cu-1Mg-Sc-Zr alloy under different conditions, including states of as-cast, homogenized, hot-rolled, as-solution and natural aged, were observed by scanning electron microscopy (SEM), X-ray diffractometry (XRD) and transmission electron microscopy (TEM). It is revealed that Sc and Zr are completely dissolved into the supersaturated solid solution in as-cast ingot, but grain refinement is not observed. Coffee-bean-like AI3(Sc, Zr) particles deposit during homogenization of ingot induce an increase in hardness. Al3(Sc, Zr) particles are slightly coarsened in as-solution samples, but they still maintain coherent to matrix, which indicates a high thermal stability of these particles. Good coherency ofAl3(Sc, Zr) particles makes some benefits for inhibiting recrystallization and reserving work-hardening.
基金
Project(2005DFA50550) supported by International Science and Technology Cooperation Program of China
Project(2005CB623705) supported by the National Basic Research Program of China