(1. 湖南大学 材料科学与工程学院，长沙 410082；
2. 湖南大学 湖南省喷射沉积技术及应用重点实验室，长沙 410082)
摘 要: 通过差热分析、金相显微镜、扫描电子显微镜、能谱分析、硬度和电导率测试等方法，对一种新型Al-Mn合金铸锭均匀化过程中的组织演变和性能变化规律进行研究。结果表明：在加热温度为560~620 ℃、保温时间为12~72 h的均匀化处理过程中，合金铸锭的电导率随温度的升高或保温时间的延长逐渐降低，但硬度先持续降低后在高于600 ℃均匀化时反而升高；合金铸锭由枝晶和晶间非平衡相组成，随均匀化温度的升高和保温时间的延长，晶间析出相逐渐溶解、球化，晶内细小弥散相大量析出；合金较优的热处理制度为600 ℃、24 h。
关键字: Al-Mn合金；均匀化；性能；显微组织；析出相
（1. College of Materials Science and Engineering, Hunan University, Changsha 410082, China;
2. Hunan Province Key Laboratory for Spray Deposition Technology and Application,
Hunan University, Changsha 410082, China）
Abstract:The evolution of microstructure and properties of a new Al-Mn alloy ingot during homogenization treatment was researched by differential scanning calorimetry (DSC), optical microscopy (OM), scanning electron microscopy (SEM), energy dispersive X-ray analysis (EDAX), as well as measurement of hardness and conductivity test, respectively. The results show that both the conductivity and the hardness of Al-Mn alloy ingot decrease with the increase of temperature in the range of 560-620 ℃ or the extension of holding time in the range of 12-72 h, but hardness at 620 ℃ is higher than that at 600 ℃. The cast alloy is composed of dendrite segregation and non-equilibrium phase. The precipitated phases gradually dissolve and become spherical, and the dispersity of precipitates within the grains increases with increasing homogenization temperature and holding time. The reasonable homogenization condition for the studied alloy is 600 ℃ and 24 h.
Key words: Al-Mn alloy; homogenization; property; microstructure; precipitated phase
