Formation behaviour of blister in cast aluminium alloy. (December 2014)

• Record Type: Journal Article
• Authors: Toda, H.; Qu, P. C.; Ito, S.; Shimizu, K.; Uesugi, K.; Takeuchi, A.; Suzuki, Y.; Kobayashi, M.
• Is Part Of: International journal of cast metals research. Volume 27:Number 6(2014)
• Page Start: 369
• Page End: 377
• Publication Date: 2014-12
• Subjects: Blister, -- Aluminium alloy, -- Micropore, -- Heat treatment, -- X-ray tomography, -- Image based simulation; Metal castings -- Periodicals; Founding -- Periodicals; Foundry research -- Periodicals; Foundry chemistry -- Periodicals; 671.2
• DOI: 10.1179/1743133614Y.0000000123
• Languages: English
• ISSNs: 1364-0461

Abstract

Abstract : The formation behaviour of a blister in a die cast aluminium alloy was observed by employing a combined methodology of in situ three-dimensional observation using X-ray microtomography and image based simulation. It has been revealed, via a reverse approach based on the simulation, that nitrogen and carbon dioxide gases fill the blister nucleus. Spontaneous growth of the blister nucleus occurs through creep deformation of the surrounding aluminium due to the blister nucleus' high internal gas pressure. This internal gas pressure also induces hydrogen precipitation in the form of micropores, which undergo steady growth in a spherical shell region around the blister nucleus. The selective growth of the micropores is attributable to the elevation of hydrostatic stress in directions parallel to the casting surface, thereby promoting the expansion of the blister, also parallel to the casting surface, through the absorption of surrounding micropores into the blister nucleus.