Characteristics of thixoformed A356 aluminum thin plates with microchannels

Bolouri, Amir; Kang, Chung Gil

Abstract

A356 aluminum thin plates with a thickness of 1.2 mm were produced via thixoforming process under different temperatures ranging from 585°C to 610°C. In addition to large primary α-Al grains, unique fine secondary α-Al grains (equivalent diameter below ∼ 8 μm) were revealed through microstructural examinations. These secondary α-Al particles exhibited irregular morphology at 590 C, which gradually transformed into equiaxed/globular grains at higher thixoforming temperatures of 605°C and 610°C. On the other hand, their size (the equivalent diameter of the grains) continuously increased from 3.2 ± 0.16 μm at 590°C to 8.1 ± 0.4 μm at 610 C. Energy dispersive X-ray spectroscopic analyses showed that the Si concentration gradually increased within these secondary α-Al grains. A quenched modified morphology consisting of angular and finely branched eutectic silicon was observed at the thixoforming temperature of 590 C, which seemed that it changed to a fibrous morphology at 605°C and 610°C. By increasing the thixoforming temperature, the elongation of the thixoformed plates monotonically increased to 12.6 ± 0.4% at 610°C, whereas the ultimate tensile strength reached its highest value of 280 ± 12 MPa at 600 C then experienced the sharp reductions at 605°C and 610°C. © 2013 Elsevier Inc.

• Journal Article Type: Article
• Acceptance Date: May 8, 2013
• Publication Date: Jun 17, 2013
• Journal: Materials Characterization
• Print ISSN: 1044-5803
• Publisher: Elsevier
• Peer Reviewed: Peer Reviewed
• Volume: 82
• Pages: 86-96
• DOI: https://doi.org/10.1016/j.matchar.2013.05.008
• Keywords: thixoforming, thin plate, aluminum alloy, microstructure, tensile behavior
• Public URL: https://uwe-repository.worktribe.com/output/936997
• Publisher URL: http://dx.doi.org/10.1016/j.matchar.2013.05.008