Eutectic nucleation in Al-7 wt pct Si-Mg casting alloys

被引：0

作者：

Chen, Zhongwei ^{[1
]}

Ma, Cuiying ^{[1
]}

Zhao, Jing ^{[1
]}

机构：

[1] Northwestern Polytech Univ, State Key Lab Solidificat Proc, Xian 710072, Peoples R China

来源：

ACTA METALLURGICA SINICA-ENGLISH LETTERS | 2012年 / 25卷 / 05期

关键词：

Al-Si-Mg alloy; Eutectic nucleation; Ce and Sr addition; DSC; SOLIDIFICATION; STRONTIUM; MICROSTRUCTURE; BETA-AL5FESI; PHOSPHORUS; MECHANISM;

D O I：

10.11890/1006-7191-125-340

中图分类号：

TF [冶金工业];

学科分类号：

0806 ;

摘要：

The nucleation of eutectic crystals of hypoeutectic Al-7 wt pct Si-Mg casting alloys modified by Ce and Sr was studied by using differential scanning calorimeter (DSC) and scanning electron microscope (SEM). DSC results were applied to calculate the values of activity energy and nucleation work of eutectic nucleation for the alloys. These values were decreased and the eutectic nucleation frequency was increased with the addition of Ce and Sr to the alloys. Moreover, the morphology of eutectic silicon in the modified alloys was partially or fully modified as fine, fibrous or coral, and DSC plots show that the eutectic undercooling of Al-7 wt pct Si-Mg alloys were increased with additions of modified agents. The mechanism of eutectic modification is combined actions of the accelerated nucleation and the restricted growth.

引用

页码：340 / 346

页数：7

共 23 条

[1] Solidification microstructures and solid-state parallels: Recent developments, future directions [J].

Asta, M. ;

Beckermann, C. ;

Karma, A. ;

Kurz, W. ;

Napolitano, R. ;

Plapp, M. ;

Purdy, G. ;

Rappaz, M. ;

Trivedi, R. .

ACTA MATERIALIA, 2009, 57 (04) :941-971

[2] Discussion of "Effect of Strontium and Phosphorus on Eutectic Al-Si Nucleation and Formation of β-Al5FeSi in Hypoeutectic Al-Si Foundry Alloys"* [J].

Campbell, John .

METALLURGICAL AND MATERIALS TRANSACTIONS A-PHYSICAL METALLURGY AND MATERIALS SCIENCE, 2009, 40A (05) :1009-1010

[3] Effect of grain refinement and modification on the dry sliding wear behaviour of eutectic Al-Si alloys [J].

Chandrashekharaiah, T. M. ;

Kori, S. A. .

TRIBOLOGY INTERNATIONAL, 2009, 42 (01) :59-65

[4] Effect of strontium and phosphorus on eutectic Al-Si nucleation and formation of β-Al5FeSi in hypoeutectic Al-Si foundry alloys [J].

Cho, Y. H. ;

Lee, H. -C. ;

Oh, K. H. ;

Dahle, A. K. .

METALLURGICAL AND MATERIALS TRANSACTIONS A-PHYSICAL METALLURGY AND MATERIALS SCIENCE, 2008, 39A (10) :2435-2448

[5]

Croseley P.E., 1966, AFS T, V74, P53

[6] Reply to discussion on "Nucleation mechanism of eutectic phases in aluminum-silicon hypoeutectic alloys' [J].

Dahle, AK ;

Hillert, M .

METALLURGICAL AND MATERIALS TRANSACTIONS A-PHYSICAL METALLURGY AND MATERIALS SCIENCE, 2006, 37A (04) :1353-1353

[7] Eutectic nucleation and growth in hypoeutectic Al-SI alloys at different strontium levels [J].

Dahle, AK ;

Nogita, K ;

Zindel, JW ;

McDonald, SD ;

Hogan, LM .

METALLURGICAL AND MATERIALS TRANSACTIONS A-PHYSICAL METALLURGY AND MATERIALS SCIENCE, 2001, 32 (04) :949-960

[8] As-cast morphology of iron-intermetallics in Al-Si foundry alloys [J].

Dinnis, CM ;

Taylor, JA ;

Dahle, AK .

SCRIPTA MATERIALIA, 2005, 53 (08) :955-958

[9]

Fisher D., 1998, FUNDAMENTALS SOLIDIF, Vfourth, P29

[10] Modification of eutectic silicon in Al-Si alloys [J].

Hegde, Sathyapal ;

Prabhu, K. Narayan .

JOURNAL OF MATERIALS SCIENCE, 2008, 43 (09) :3009-3027

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