(1. 南昌航空大学 江西省金属材料微结构调控重点实验室，南昌 330063;
2. 南昌航空大学 轻合金加工科学与技术国防重点实验室，南昌 330063;
3. 中国航发南方工业有限公司，株洲 412002)
摘 要: 采用旋转摩擦挤压法(RFE)制备了不同Mg含量的Al-Mg铝合金，对其进行力学性能测试和显微组织观察。结果表明：退火态的5A06基材经RFE加工后，晶粒明显细化，抗拉强度和伸长率同时提高。采用5A06和AZ31B为基材经RFE加工制备Al-Mg合金后，合金抗拉强度随Mg含量的增加而增加，但伸长率却随合金Mg含量的增加而降低；高Mg含量的Al-Mg合金晶粒可进一步细化，这是由于高Mg含量的Al-Mg合金中存在Al3Mg2相，可以作为动态再结晶的形核点，促进动态再结晶。然而，Al3Mg2相的存在会降低合金的伸长率。
关键字: Al-Mg合金；旋转摩擦挤压；晶粒；Al3Mg2相
（1. Key Laboratory for Microstructural Control of Metallic Materials of Jiangxi Province, Nanchang Hangkong University, Nanchang 330063, China;
2. National Defense Key Disciplines Laboratory of Light Alloy Processing Science and Technology, Nanchang Hangkong University, Nanchang 330063, China;
3. AECC South Industry Company, Zhuzhou 412002, China）
Abstract:The Al-Mg aluminum alloys with different Mg contents were prepared by rotational friction extrusion (RFE). Their mechanical properties were tested and the microstructures were observed. The results show that the grains of the annealed 5A06 substrate after RFE processing are significantly refined. The ultimate tensile strength and elongation both increase. While the tensile strengths of Al-Mg alloys using the 5A06 and AZ31B as raw materials after RFE processing increase as the addition of Mg content increases, but the elongations decrease. Meanwhile, the grains of the Al-Mg alloy with high Mg content after RFE processing are further refined. The reason is due to the formation of Al3Mg2 phase in the Al-Mg alloy with high Mg content. The Al3Mg2 phase as the nucleation site of dynamic recrystallization, can promote the process of dynamic recrystallization. However, the existence of Al3Mg2 will reduce the elongation of Al-Mg alloys.
Key words: Al-Mg alloy; rotational friction extrusion; grain; Al3Mg2 phase
