View in EDS

Semi-solid behavior of new Al–Si–Mg alloys for thixoforming

Saved in:

Bibliographic Details
Title:	Semi-solid behavior of new Al–Si–Mg alloys for thixoforming
Authors:	Paes, M.¹, Zoqui, E.J. zoqui@fem.unicamp.br
Source:	Materials Science & Engineering: A. Oct2005, Vol. 406 Issue 1/2, p63-73. 11p.
Subjects:	Metallic composites, Magnesium alloys, High temperatures, Rheology
Abstract:	Abstract: There is a lack of specific alloys for thixoforming processes. Usually alloys from conventional casting processes were fitted to the thixoforming purpose, e.g. A356, A357. The aim of this study is to produce new Al–Si–Mg alloys specially tailored for thixoforming purpose. The as-rheocast: Al–7wt%Si–0.5wt%Mg, Al–4wt%Si–0.5wt%Mg, Al–1wt%Si–0.5wt%Mg, Al–7wt%Si–1wt%Mg, Al–4wt%Si–1wt%Mg and Al–1wt%Si–1wt%Mg were produced by grain refining. Thus, the effect of Si and Mg content on structure and rheological behavior of these new alloys was analyzed. To simulate the semi-solid behavior at a high temperature, the samples were re-heated to the semi-solid state to produce 45% solid fraction and their structural evolution was analyzed after 0, 90 and 210s at this solid fraction. At the same temperature and holding time, the samples were submitted to a compression test using a parallel platen viscosimeter. Results showed that the grain/globule size increased as the Si and Mg content increased. Al–7wt%Si–0.5wt%Mg, the Al–4wt%Si–0.5wt%Mg and the Al–1wt%Si–0.5wt%Mg are suitable for thixoforming purposes. Al–Si alloys with 1.0wt%Mg showed low apparent viscosity values. [Copyright &y& Elsevier]
	Copyright of Materials Science & Engineering: A is the property of Elsevier B.V. and its content may not be copied or emailed to multiple sites without the copyright holder's express written permission. Additionally, content may not be used with any artificial intelligence tools or machine learning technologies. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
Database:	Engineering Source

Description
Abstract:	Abstract: There is a lack of specific alloys for thixoforming processes. Usually alloys from conventional casting processes were fitted to the thixoforming purpose, e.g. A356, A357. The aim of this study is to produce new Al–Si–Mg alloys specially tailored for thixoforming purpose. The as-rheocast: Al–7wt%Si–0.5wt%Mg, Al–4wt%Si–0.5wt%Mg, Al–1wt%Si–0.5wt%Mg, Al–7wt%Si–1wt%Mg, Al–4wt%Si–1wt%Mg and Al–1wt%Si–1wt%Mg were produced by grain refining. Thus, the effect of Si and Mg content on structure and rheological behavior of these new alloys was analyzed. To simulate the semi-solid behavior at a high temperature, the samples were re-heated to the semi-solid state to produce 45% solid fraction and their structural evolution was analyzed after 0, 90 and 210s at this solid fraction. At the same temperature and holding time, the samples were submitted to a compression test using a parallel platen viscosimeter. Results showed that the grain/globule size increased as the Si and Mg content increased. Al–7wt%Si–0.5wt%Mg, the Al–4wt%Si–0.5wt%Mg and the Al–1wt%Si–0.5wt%Mg are suitable for thixoforming purposes. Al–Si alloys with 1.0wt%Mg showed low apparent viscosity values. [Copyright &y& Elsevier]
ISSN:	09215093
DOI:	10.1016/j.msea.2005.07.018