Volume 38, Number 2, April 2020
|Page(s)||384 - 391|
|Published online||17 July 2020|
Microstructure Characteristic and Fatigue Damage Behaviors of 2060 Al-Li Alloy Thin Plate
Beijing Institute of Aeronautical Materials, Beijing 100095, China
2 Beijing Engineering Research Center of Advanced Aluminum Alloys and Applications, Beijing 100095, China
3 Key Lab of Electromagnetic Processing of Materials, Northeastern university, Shenyang 110819, China
The microstructure characteristic, fatigue damage behaviours and evolution of microstructure during the fatigue testing of 2060 Al-Li alloy thin plate were studied by fatigue tester equipped with in-situ observation device, OM, EBSD, SEM and TEM. The results show that recrystallized grains with irregularity shape and large size are observed, the Goss and Cube texture are the mainly types, abundant of T1 with size of 50~60nm are found in grains. During axial loaded fatigue testing, a crack initiates from the edge of sample and extend into grain along the direction with maximum Schmid factor. When the crack reaches and crosses the first grain boundary, the extending direction deflects from 45° degree to perpendicular with loading direction, and propagates along this direction till the sample quickly fracture. A large size deformation region contains numerous slip strips around the crack tip during the initiation and extending process is observed. The dislocations cut across the T1 precipitates located in grains during deformation, and release the stress concentration on the crack tip. The fatigue crack extends across the grains with serrated shape can result from the big orientation difference of grains and easy screwed T1 precipitates.
Key words: 2060 Al-Li alloy / axial loaded fatigue testing / fatigue damage behavior / texture / T1 precipitate / Schmid factor / crack extending / stress concentration
关键字 : 2060铝锂合金 / 轴向疲劳试验 / 疲劳损伤行为 / 织构 / T1析出相 / Schmid因子 / 裂纹扩展 / 应力集中
© 2019 Journal of Northwestern Polytechnical University. All rights reserved.
This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
Current usage metrics show cumulative count of Article Views (full-text article views including HTML views, PDF and ePub downloads, according to the available data) and Abstracts Views on Vision4Press platform.
Data correspond to usage on the plateform after 2015. The current usage metrics is available 48-96 hours after online publication and is updated daily on week days.
Initial download of the metrics may take a while.