采用X射线衍射仪、能谱仪和透射电镜分别对Al-9.6％Mg合金、Al- 11Mg-4.5Zn合金和Al- 17Zn- 1.5Mg合金常压及6 GPa高压凝固后Al相的固溶体结构进行研究.结果表明:6GPa高压凝固后,Al-9.6％Mg合金中Mg在Al相中的固溶度显著增大:在Al-11Mg-4.5Zn合金和Al- 17Zn- 1.5Mg合金中,Mg、Zn溶质在Al相中的固溶度均增大,但Zn比Mg固溶的比例要大得多.在常压凝固条件下,与纯铝相比,3种合金中Al相的晶格常数均增大.与常压凝固相比,高压凝固Al-9.6Mg合金和Al-11Mg-4.5Zn中Al相晶格常数分别增大了1.178％和0.220％;在Al- 17Zn- 1.5Mg合金中,Al相晶格常数变化很小.此外,在Al-Mg-Zn合金中,原子半径较大的Mg固溶到Al相中,导致其晶格常数增大,原子半径较小的Zn固溶到Al相中,导致其晶格常数减小,且高压凝固后,溶质的原子半径越小,在Al相中固溶的比例越大.%The solid solution structures of Al phases in Al-9.6%Mg, Al-llMg-4.5Zn andAl-17Zn-1.5Mg alloys solidified under normal pressure and high pressure were investigated using XRD, EDS and TEM. The results show that the solid solubility of Mg in Al phase in Al-9.6%Mg alloy increases remarkably, and those of Mg and Zn in Al phase in Al-llMg-4.5Zn and Al-17Zn-1.5Mg alloys increase, however, the proportion of Zn saturating in Al phase is much more than that of Mg. Under the condition of normal pressure solidification, the lattice constants of Al phases in three alloys have an increment comparing with that of pure Al. In contrast to normal pressure solidification, the lattice constants of Al phases in Al-9.6Mg alloy and AI-llMg-4.5Zn alloy solidifying at 6 GPa high pressure increase up to 1.178% and 0.220%, respectively. And the lattice constant of Al phase in AI-17Zn-1.5Mg alloy changes little. Furthermore, Mg with larger atomic radius saturating in Al phase leads to the increment of the lattice constant in Al-Mg-Zn alloy, and that of Zn with smaller atomic radium causes the lattice constant to decrease. The smaller the atomic radium of the solute is, the more the proportion saturates in Al phase after high pressure solidification are.
展开▼
