(1. 中南大学 材料科学与工程学院，长沙 410083；
2. 中南大学 有色金属材料科学与工程教育部重点实验室，长沙 410083；
3. 航天材料及工艺研究所，北京 100076)
摘 要: 利用新型的薄板叠层端淬法结合时效后强度变化，评价2060铝锂合金的淬透性，并采用扫描电子显微镜(SEM)、透射电子显微镜(TEM)、场发射透射电子显微镜(STEM)及能谱(EDS)对末端淬火并T8时效后的微观组织进行了分析。结果表明：以抗拉强度下降5%作为淬透深度的判断依据，则2060铝锂合金的淬透深度约为15 mm。随着距淬火端距离的增大，抗拉强度依次降低直至稳定，但在距淬火端12~18 mm的区间内，强度发生较明显变化。端淬过程中析出的富Cu相降低了固溶体过饱和程度，阻碍后续时效过程中同一位置T1相(Al2CuLi)的析出和长大，导致合金抗拉强度逐渐减小。
关键字: 2060铝锂合金；淬透性；强度；微观组织
（1. School of Materials Science and Engineering, Central South University, Changsha 410083, China;
2. Key Laboratory of Nonferrous Mental Materials Science and Engineering, Ministry of Education, Changsha 410083, China;
3. Aerospace Research Institute of Materials and Processing Technology, Beijing 100076, China）
Abstract:The harden ability of 2060 Al-Li alloy was experimentally evaluated by using cold-rolled thin sheets, which combined end-quenching with strength change after aging. The scanning electron microscopy(SEM), transmission electron microscopy(TEM), scanning transmission electron microscopy(STEM) and energy dispersive spectrometer(EDS) were used to analyze the microstructure of samples with T8-aging following end-quenching. The results show that the quenching depth of 2060 Al-Li alloy is 15 mm, the tensile strength is reduced by 5% is defined as the quenching depth. With the distance away from the quenching end increasing, the tensile strength gradually decreases to a stable level. Moreover, there is a significant decreasing in the tensile strength at the location from 12 mm to 18 mm. During the end-quenching process, the Cu-rich phase which reduces the supersaturation of the solid solution precipitates and hinders the precipitation and growth of T1 phase(Al2CuLi) in the same region during the subsequent aging process. The tensile strength is therefore decreased gradually.
Key words: 2060 Al-Li alloy; hardenability; strength; microstructure
