Han Seung Zeon, Ryu Byungki, Jeong Il-Seok, Lim Sung Hwan, Choi Eun-Ae
Extreme Materials Institute, Korea Institute of Materials Science (KIMS), Changwon, 642-831, South Korea.
Energy Conversion ResearchCenter, Korea Electrotechnology Research Institute (KERI), Changwon, 51543, South Korea.
Heliyon. 2024 Jul 20;10(14):e34984. doi: 10.1016/j.heliyon.2024.e34984. eCollection 2024 Jul 30.
The Zn element precipitates during aging in the Al-Zn binary alloy. Increased Zn content and prolonged aging leads to discontinuous Zn precipitation. The addition of 2 wt% Cu to the Al-43 wt%Zn alloy accelerates this discontinuous precipitation, resulting in decreased thickness of Zn layers and inter-distance between them. This acceleration is attributed to the influence of Cu solutes on the Zn phase, thereby reducing the interface energy between Zn precipitates and the Al matrix. The Al-Zn-Cu alloy demonstrates exceptional behavior during tensile tests, displaying a simultaneous increase in tensile strength and ductility alongside an 75 % reduction in area at room temperature drawing. Notably, despite the drawn beyond uniform deformation limit, there is an observed increase in total elongation. Our demonstration highlights this phenomenon, attributing it to the sustained coherent interface between the Zn layer and the Al matrix, as well as the uninterrupted continuity of Zn layers during drawing.
在Al-Zn二元合金时效过程中，锌元素会析出。锌含量增加及时效时间延长会导致不连续的锌析出。向Al-43 wt%Zn合金中添加2 wt%的铜会加速这种不连续析出，导致锌层厚度及其间距减小。这种加速归因于铜溶质对锌相的影响，从而降低了锌析出物与铝基体之间的界面能。Al-Zn-Cu合金在拉伸试验中表现出特殊行为，在室温拉伸时，抗拉强度和延展性同时增加，断面收缩率降低75%。值得注意的是，尽管拉伸超过了均匀变形极限，但总伸长率仍有所增加。我们的论证突出了这一现象，将其归因于锌层与铝基体之间持续的共格界面，以及拉伸过程中锌层的不间断连续性。
