期刊
MATERIALS & DESIGN
卷 119, 期 -, 页码 54-64出版社
ELSEVIER SCI LTD
DOI: 10.1016/j.matdes.2017.01.058
关键词
Al-Cu-Li alloy; Thermal effect; Hardness test; Tensile test; Microstructure; STEM
资金
- Research council of Norway
- NTNU
- SINTEF
- Research Council of Norway through the FRINATEK [221714]
The thermal stability of the lightweight T83 heat treated 2099 Al-Cu-Li alloy was assessed in the temperature range 200-305 degrees C, through both hardness and tensile tests after overaging. After prolonged thermal exposure, the alloy exhibited a better performance compared to aluminium alloys specifically developed for high temperature applications, with the advantage of a considerable lower density. The tensile behaviour was modelled through Hollomon's equation as a function of residual hardness. The changes in the alloy performance were explained through both SEM and STEM investigations. Microstructural analyses gave evidence of Ostwald ripening, while fractographic analyses revealed a transition from an intergranular to a ductile fracture mechanism in the overaged alloy. STEM investigations highlighted the superior thermal stability of the T-1 phase compared to theta and S strengthening phases, which dissolved during overaging at 245 degrees C. The study underlines the need to enhance the formation of T-1 precipitates when high temperature strength is required. The results of the present study suggest that the 2099 alloy is a very promising candidate for automotive engine components, which are extremely demanding in terms of both thermal resistance and lightweight. (C) 2017 Elsevier Ltd. All rights reserved.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据