(1. 北京有色金屬研究總院有色金屬材料制備加工國家重點實驗室，北京 100088；
2. 北京有色金屬研究總院有色金屬加工中心，北京 100088)
摘 要: 對2197鋁鋰合金進行形變熱處理，采用HREM高分辨電鏡觀察合金欠時效和峰時效兩個階段的顯微組織，研究T1相析出長大行為及其界面特征。結(jié)果表明：形變熱處理2197合金在欠時效階段主要存在δ′、θ′和T1相，T1相尺寸約為40 nm；峰時效階段合金中δ′和θ′數(shù)量減少，主要析出相為T1相，其尺寸為50~150 nm，T1相可通過δ′相的溶解而長大。在欠時效和峰時效兩階段，T1相末端與基體共格，其他區(qū)域與基體非共格。T1相為六方晶系，與基體存在慣析關系：(0001)T1//(111)A1、[1010]T1//[110]A1，慣析面為{111}A1。
關鍵字: 2197 Al-Li合金；形變熱處理；T1相；析出行為
（1. State Key Laboratory of Nonferrous Metals and Processes,
General Research Institute for Nonferrous Metals, Beijing 100088, China;
2. Nonferrous Metals Processing Division, General Research Institute for Nonferrous Metals, Beijing 100088, China）
Abstract:2197 Al-Li alloy was thermo-mechanically treated, and the precipitation and growth of the T1 phase and the phase interface characteristics were studied. The microstructures of thermo-mechanical treated 2197 Al-Li alloy for under-aged and peak-aged states were observed by high resolution electron microscopy (HREM). The results show that during thermo-mechanical treatment, δ′, θ′ and T1 phases are the main phases of under-aged 2197 alloy, the size of T1 phase is about 40 nm. δ′ and θ′ phases number reduce at peak-aged state, while the main phase of peak-aged 2197 alloy is T1 phase with the size of 50-150 nm. The T1 phase grows up by the dissolving of δ′ phase. The end of T1 phase of peak-aged 2197 alloy is coherent with the matrix while the rest is non-coherent during under-aged and peak-aged states. Habit relationships between T1 phase which is hexagonal crystal system and the matrix is as follow: (0001)T1//(111)A1 and [1010]T1//[110] A1, and the habit plane is {111}A1.
Key words: 2197 Al-Li alloy; thermo-mechanical treatment; T1 phase; precipitation behavior
