AA2050鋁合金常溫與高溫變形下差排與析出物交互作用
Other Title
The interaction between dislocation and precipitate under ambient and high temperatures in an AA 2050 aluminum alloy
Journal
真空科技
Journal Volume
37
Journal Issue
1
Start Page
7-1
End Page
7-9
ISSN
1017-091X
Date Issued
2024-03
Author(s)
Abstract
AA2050鋁銅鋰合金展現出高強度、輕量化和良好的耐蝕性等優異性能，因此廣泛應用於航空材料。在AA2050鋁合金中，強化效果的貢獻主要來自T_1相的析出，該析出相在母相基地的｛111｝_(Al)面上以盤狀結構形式存在於鋁合金材料內部。本研究聚焦於AA2050鋁銅鋰合金之析出物T_1於不同溫度下與差排間的交互作用。本研究透過穿透式電子顯微鏡的拍攝TEM明場影像及HRTEM影像發現差排剪切的T_1之形貌，進一步發現在不同溫度下，析出物T_1與差排的交互作用有明顯差異。低溫下差排對T_1同一處僅會進行單一次剪切，值得注意的是，對於同一T_1析出物而言，每一次剪切事件發生之間距在常溫下為2至5奈米，而高溫拉伸試片中觀測到的交互作用情形相較於常溫拉伸試片更加劇烈，被剪切的T_1之形貌更加不規則，剪切現象的發生更加頻繁密集。
AA2050 Al-Cu-Li alloys are widely used in aerospace industries due to their high strength, low density and good damage tolerance. Among AA2050 aluminum alloys, the precipitation of T_1 phase provides the main contribution of strengthening. T_1 phase is identified as platelet-shaped precipitate, lying on habit planes of {111}_(Al) in the aluminum matrix. In this work, the interaction of dislocation and T_1 phase at ambient and high temperatures in an AA2050 Al-Cu-Li alloy has been investigated. At the ambient temperature, TEM and HRTEM observations indicated that single shearing events were energetically preferred regardless of the thicknesses of T_1 precipitates. It is worth noting that the distance between every single shearing step falls in a range of 2-5 nm for room temperature tensile test specimens. However, it is of interest to evaluate more precisely on those high temperature tensile test samples since the phenomena of the dislocation-precipitate interactions observed were relatively more complex and individualized.
Subjects
AA2050鋁銅鋰合金
析出硬化
奈米析出物T_1相
高解析穿透式電子顯微鏡
AA2050 Al-Cu-Li alloys
Precipitation hardening
T_1 phase
High resolution transmission electron microscope
Type
journal article