中文摘要：

为了在微观结构，阶段作文和当演员组 Mg-6Zn-1.4Y-0.6Zr 合金，在 440 oC 的答案处理， 460 oC 和 480 oC 和进一步的老化的机械性质上调查答案温度和我阶段的分解的效果，处理在合金上被进行。结果显示网状的金属间化合的混合物(主要我阶段) 从 440 oC 随答案温度的增加逐渐地溶解进 -Mg 矩阵到 480 oC。而且，我阶段在 480 oC 完全分解，与好 W 阶段(热稳定的阶段) 和 Mg ₇ Zn ₃ 阶段。另外，很多好、散的 Mg-Zn 二进制阶段在变老的处理期间在 -Mg 矩阵猛抛。由于溶质原子的增加和加强阶段的降水，例如 W 阶段和 Mg-Zn 阶段，最佳的力量为 8 h 在 460 oC 在溶液处理以后被获得并且为 16 h 在 200 oC 变老。收益力量(YS ) ，最终的张力的力量(UTS ) 和延伸是 208 MPa， 257 MPa 并且 3.8% 分别地。与当演员组合金相比，分别地，当延伸的减少是 46% 时， YS 和 UTS 的增长是 117% 和 58% 。

英文摘要：

To investigate the effects of solution temperature and the decomposition of I-phase on the microstructure, phase composition and mechanical properties of as-cast Mg-6Zn-1.4Y-0.6Zr alloy, solution treatment at 440 oC, 460 oC and 480 oC and further aging treatment were conducted on the alloy. The results indicate that the net-like intermetallic compounds（mainly I-phase） dissolve into the α-Mg matrix gradually with the increase of solution temperature from 440 oC to 480 oC. Besides, the I-phase decomposes completely at 480 oC, with the formation of fine W-phase（thermal stable phase） and Mg_7Zn_3 phase. In addition, a great number of fine and dispersive Mg-Zn binary phases precipitate in the α-Mg matrix during the aging treatment. Due to the increase of solute atoms and the precipitation of strengthening phases, such as W-phase and Mg-Zn phases, the optimal strength is obtained after solution treatment at 460 oC for 8 h and aged at 200 oC for 16 h. The yield strength（YS）, ultimate tensile strength（UTS） and elongation are 208 MPa, 257 MPa and 3.8%, respectively. Compared with the as-cast alloy, the increments of YS and UTS are 117% and 58%, respectively, while the decrement of elongation is 46%.