摘要： Iron is the most deleterious impurity in aluminum alloys and can easily combine with aluminum to form an acicular β-Al5FeSi phase that reduces ductility during the solidification of the molten metal. Adding scandium (Sc) to Al–7Si–0.6Mg alloys can transform the acicular β-Al5FeSi phase into a comparatively harmless nodular Sc–Fe phase (Al12Si6Fe2(Mg,Sc)5). This Sc–Fe phase has a lower hardness and elastic modulus than the β-Al5FeSi phase; it is thus less likely to initiate cracks in the Al matrix. Moreover, the nodular Sc–Fe phase can improve the fluidity of Al during solidification, reducing interdendritic shrinkage. Tensile testing measurements showed that the elongation of Al–7Si–0.6Mg alloys with 0.04 and 0.12wt% Sc can be respectively increased by 115% and 110% compared to Al–7Si–0.6Mg without Sc. The corresponding quality indices are increased by 17% and 19%, respectively, suggesting that the tensile properties of Al–7Si–0.6Mg alloys can be enhanced by adding scandium. 出版者： Kidlington: Elsevier B.V 出版日期： 2014-01 出處： Materials Science and Engineering: A, 2014-01, Vol.593, p.103-110 版權： 2013 Elsevier B.V. 版權： 2015 INIST-CNRS 識別號： ISSN: 0921-5093 識別號： EISSN: 1873-4936 識別號： DOI: 10.1016/j.msea.2013.11.039
