Study on Eutectic Microstructure and Modification Mechanism of Al-Si Alloys

Jian Xun Chen; Meng Jie Lu; Shu Sen Wu; Shu Lin Lü

doi:10.4028/www.scientific.net/MSF.877.97

Paper Titles

Supersaturation Behavior of Al Solid Solutions and its Effect on Tensile Property in Al-7Si-xMg Alloys during Solution Heat Treatment (x: 0.4 and 0.8 Mass%)
p.73

Evaluation on the Accuracies of Sump Depth Measurements during DC Casting Process of 7050 Alloy
p.78

Effect of Electromagnetic Field on the Macrosegregation Behaviour of Al-Cu Alloy Ingot Prepared with Direct-Chill Casting Process
p.84

Tensile Deformation Behavior of Al-Cu 206 Cast Alloys near the Solidus Temperature
p.90

Study on Eutectic Microstructure and Modification Mechanism of Al-Si Alloys
p.97

Grain Refinement in an Al-Zn-Mg-Cu Casting Ingot
p.104

Effects of Si Addition on the Microstructure and Tensile Property of Al-xMg Alloys with Al₂Ca during Heat Treatment (x: 5 and 7 Mass%)
p.109

Research of Preparing Parameters in the Complex Process on Microstructure in Semisolid A356 Alloy Slurry with Micro-Addition of La
p.114

Effects of Ti Powder Additions in Melt-SHS Process on the Performance of Al-Ti-B Grain Refiner Alloys
p.121

HomeMaterials Science ForumMaterials Science Forum Vol. 877Study on Eutectic Microstructure and Modification...

Study on Eutectic Microstructure and Modification Mechanism of Al-Si Alloys

Abstract:

Sb is an effective additive to modify eutectic Si of Al-Si alloys and the modification mechanism has not yet been studied very clearly. In this paper, computer aided cooling curve thermal analysis and microstructure assessment were carried out to investigate the modification effects of Sb on Al7SiMg alloy. The results show that the Sb addition amount of 0.1~0.25% has improvement effect on eutectic Si morphology, which can be further confirmed from the thermal analysis results. The addition of Sb decreases the eutectic growth temperature by 5 °C to 7.8 °C, indicating an undercooling effect resulted from Sb modification. Compared to that of short rods, a better eutectic Si morphology of nearly granular particles can be obtained in a faster cooling rate. The length of silicon has been gradually shortened as holding time increased to 2.5 h from 0.5 h, which means a long period modification effect of Sb in Al-Si alloys. Owing to undercooling resulted from Sb addition in Al-Si alloys, the refinement structure of eutectic silicon can be achieved.

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Periodical:

Materials Science Forum (Volume 877)

Pages:

97-103

DOI:

https://doi.org/10.4028/www.scientific.net/MSF.877.97

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Online since:

November 2016

Authors:

Jian Xun Chen, Meng Jie Lu, Shu Sen Wu*, Shu Lin Lü

Keywords:

Al7SiMg, Antimony, Eutectic Si, Modification, Thermal Analysis

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