(1. 沈阳航空航天大学 材料科学与工程学院，沈阳 110136；
2. 齐鲁工业大学(山东省科学院)新材料研究所 山东省轻质高强金属材料重点实验室，济南 250014)
摘 要: 以AZ系镁合金(AZ31、AZ80和AZ91)中的Al-Mn相作为研究对象，利用OM、SEM和EPMA等方法研究Al-Mn相在AZ系镁合金中的分布和形成，讨论Al-Mn相在晶内、晶界及氧化物夹杂处的组成，及Al-Mn相在氧化物夹杂处析出机理。结果表明：AZ系镁合金中的Al-Mn相主要为颗粒状、棒状和不规则块状，尺寸均小于30 μm，主要分布在初生α-Mg、β-Mgl7Al12相和晶界处，呈弥散分布形态； Al-Mn相为Al8Mn5或Al8(Mn,Fe)5。AZ系合金中的氧化物夹杂MgO能够诱发Al8Mn5相在其周围以聚集分布的形式析出；通过分析Al8Mn5相在MgO夹杂处形成、富集机理，获得Al8Mn5相在AZ系镁合金中MgO夹杂处形核长大的析出模式。
关键字: AZ系镁合金；Al-Mn相；氧化物夹杂；分布；形成机理
（1. School of Material Science and Engineering, Shenyang Aerospace University, Shenyang 110136, China;
2. Shandong Key Laboratory for High Strength Lightweight Metallic Materials Institute, Qilu University of Technology (Shandong Academy of Sciences), Ji’nan 250014, China）
Abstract:The distribution and formation of Al-Mn phase in AZ series magnesium alloys (AZ31, AZ80, and AZ91) were investigated by OM, SEM and EPMA. The composition of Al-Mn phase on grains, grain boundary and oxide inclusions, as well as the precipitation mechanism of Al-Mn phase on the oxide inclusions was discussed. The results show that the Al-Mn phases in AZ system magnesium alloys are mainly granular, rod-like and irregular block, with size of less than 30 μm. Al8Mn5 or Al8(Mn,Fe)5 are dispersed on the primary α-Mg, β-Mgl7Al12 phase and grain boundary. The entrained MgO in AZ series alloys can induce the precipitation of Al8Mn5 particles which cluster around MgO. The mechanism of formation and enrichment of Al8Mn5 on MgO is analyzed, and the precipitation modes of nucleation and growth of Al8Mn5 phase on MgO in the AZ series magnesium alloys are obtained.
Key words: AZ Series magnesium alloys; Al-Mn phase; oxide inclusion; distribution; formation
