Structure Heredity Effect of Mg-10Y Master Alloy in AZ31 Magnesium Alloy

摘要:

不同制备方法而具有相同组织的Mg-10Y中间合金具有明显不同的变质效果和遗传效应。结果表明：常规铸态、挤压态、热处理态和快速凝固态Mg-10Y中间合金组织和晶粒尺寸存在差异。Mg-10Y中间合金作为变质剂加入到AZ31中具有明显的细化效果。最终镁合金组织均由α-Mg, Mg17Al12, Al2Y和Al3Y相组成。添加挤压态Mg-10Y中间合金的AZ31镁合金机械性能达到最优，抗拉强度和延伸率分别为199.3 MPa和9.2%。Mg-10Y中间合金与所对应的镁合金存在相似的组织形态，这种结构和机械性能的相关性与Mg-10Y中间合金的结构遗传有关。

Abstract:

The Mg-10Y master alloys made by different processes but with the same composition have obviously different modifying efficiencies and structure heredity effects. The results indicate that there exist differences in the microstructures and grain sizes of Mg-10Y master alloys in the states of conventional casting, as-extruded, heat-treated and rapid solidification. The Mg-10Y master alloys are added to AZ31 magnesium alloy as modifier and an obvious refinement is observed. The final magnesium alloys are all composed of α-Mg, Mg17Al12, Al2Y and Al3Y phases. Similar structures exist in both the Mg-10Y master alloys and the final magnesium alloys. After addition of as-extruded Mg-10Y master alloy, the mechanical properties of AZ31 alloy reach the maximum at room temperature, whose ultimate tensile strength is up to 199.3 MPa and the elongation is up to 9.2%. The corresponding differences of the microstructures and the mechanical properties between Mg-10Y master alloys and AZ31 magnesium alloy are related to the structure heredity of Mg-10Y master alloys.