(1. 中國船舶重工集團公司 第七二五研究所，洛陽 471039； 2. 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)
摘 要: 采用硬度測試、力學性能測試、SEM、EDS和TEM分析等方法，研究不同固溶處理和時效處理制度對新型Al-Cu-Li合金組織與性能的影響。結果表明：合金經(jīng)490 ℃、1.5 h固溶處理后，第二相粒子回溶充分，未回溶第二相為AlCuFeMn相，合金斷口形貌呈沿晶斷裂與少量韌窩形貌混合特征。合金適宜的T6制度為175 ℃、48 h，抗拉強度、屈服強度和伸長率分別為447 MPa、369 MPa和8.9%。適宜的T8制度為預變形6%+(160 ℃、36 h)，抗拉強度、屈服強度和伸長率分別為500 MPa、454 MPa和10.5%，此時合金具有較好的強塑性匹配。合金在T6和T8態(tài)的強化相均為復合相δ′/β′相、θ′相和T1相3種。時效前的預變形可顯著提高合金強度，隨預變形量的增加，合金強化相由δ′/β′相、θ′相和T1相為主逐漸轉向以T1相為主，T1相比θ′相、δ′相具有更佳的強化效果。
關鍵字: Al-Cu-Li合金；固溶處理；時效處理；力學性能
（1. Luoyang Ship Material Research Institute, Luoyang 471039, China; 2. State Key Laboratory of Nonferrous Metals and Processes, General Research Institute for Nonferrous Metals, Beijing 100088, China）
Abstract:The relationship between microstructures and properties of a new Al-Cu-Li alloy under different solid solution and aging treatments were studied by hardness test, tensile test, SEM, EDS and TEM analysis. The results show that the second phase particles of the alloy are fully dissolved by solid solution treatment at 490 ℃ for 1.5 h, and the remaining second phase is AlCuFeMn phase. The fracture mode of the alloy is characterized by intergranular fracture and small dimple mixed fracture. The suitable T6 temper of the alloy is (175 ℃, 48 h), and the corresponding tensile strength, yield strength and elongation rate are 447 MPa, 369 MPa and 8.9%, respectively. The suitable T8 temper of the alloy is 6%+(160 ℃, 36 h), and the corresponding tensile strength, yield strength and elongation rate are 500 MPa, 454 MPa and 10.5%, respectively. The alloy shows excellent combination of strength and ductility when the pre-deformation ratio is controlled at about 6%. The strength phase of the alloy are composite phase δ′/β′, θ′ and T1 in T6 and T8 temper. The pre-deformation greatly improves the strength of the alloy. With the increase of the pre-deformation, the mainly strengthening phase of the alloy gradually change from δ′/β′, θ′ and T1 to the T1 phase. T1 has better strengthening effect compared with δ′/β′ phase and θ′ phase.
Key words: Al-Cu-Li alloy; solid solution treatment; aging treatment; mechanical property
