【摘要】 研究了Ｓｎ对镁合金显微组织和力学性能的影响。研究结果表明，纯镁中加入Ｓｎ后能使纯镁铸锭中粗大的柱状晶转化为均匀的等轴晶，并有效地细化晶粒，同时在显微组织中形成具有立方Ｃ１结构的Ｍｇ２Ｓｎ颗粒相。由于Ｍｇ２Ｓｎ颗粒相显微硬度和熔点高，热稳定性好，因而对基体具有有效的弥散强化作用，提高了ＭｇＳｎ二元合金的室温及高温强度。在Ｍｇ９Ａｌ０．８Ｚｎ基合金中加入少量的Ｓｎ便能有效地提高合金的耐热性，而加入过多的Ｓｎ反而会导致合金高温强度下降。更多还原

【Abstract】 Effects of Sn addition on the microstructure and mechanical properties of magnesium alloys were studied. Results showed that the Sn addition to magnesium modifies the microstructure of magnesium ingot and causes the formation of Mg 2Sn precipitates with C1 cubic structure. The strength of Mg Sn alloy has increased at both ambient and elevated temperatures due to the high micro hardness and melting point as well as the high thermal stability of the precipitates. In the ternary alloy of Mg 9Al 0.8Zn small amount addition of Sn results in significant improvement of heat resistance. However, the excessive Sn addition to Mg 9Al 0.8Zn leads to the decrease of the strength at elevated temperature.更多还原