Microstructure evolution of 2024 and 7A09 aluminium alloys subjected to thermal cycling in simulated LEO space environment. (June 2014)

• Record Type: Journal Article
• Authors: Lv, P.; Zhang, Z.; Wang, X.; Ji, L.; Hou, X.; Guan, Q.
• Is Part Of: Materials research innovations. Volume 18:Number 3(2014)
• Page Start: 169
• Page End: 175
• Publication Date: 2014-06
• Subjects: Materials -- Research -- Periodicals; Matériaux -- Recherche -- Périodiques; 620.1105
• DOI: 10.1179/1433075X13Y.0000000182
• Languages: English
• ISSNs: 1432-8917

Abstract

<abstract> <title> <x content-type="archive" xml:space="preserve">Abstract</x> </title> <p>The microstructures and properties of 2024 and 7A09 aeronautical aluminium alloys subjected to thermal cycling have been investigated in simulated low earth orbit (LEO) space environment using microhardness tests, X-ray diffraction (XRD) and transmission electron microscopy (TEM). The microhardness tests revealed that the hardness decrease first and then increase, but finally decrease with the cycle times. The results of XRD and TEM show that, in 2024 aluminium alloy, the precipitate evolution with the cycling time is the small needle-like S′ phases transforming to the rod-like equilibrium S phases. In 7A09 aluminium alloys, needle-like <italic>η</italic>′ phases and short rod-like <italic>η</italic> equilibrium phases transform to rod-like <italic>η</italic> equilibrium phases and large size of Guinier–Preston zones in the process of thermal cycling. Furthermore, many cavities around the precipitated phase appear after 500 cycles in both 2024 and 7A09 aluminium alloys. The relationship between microstructural evolution and thermal fatigue in LEO space environment was discussed.</p> </abstract>