Nanoparticle-inhibited growth of primary aluminum in Al-10Si alloys

被引：137

作者：

Wang, K. ^{[1
,2
]}

Jiang, H. Y. ^{[1
,2
]}

Jia, Y. W. ^{[1
,2
]}

Zhou, H. ^{[1
,2
]}

Wang, Q. D. ^{[1
,2
]}

Ye, B. ^{[1
,2
]}

Ding, W. J. ^{[1
,2
]}

机构：

[1] Shanghai Jiao Tong Univ, Natl Engn Res Ctr Light Alloys, Net Forming, Shanghai 200240, Peoples R China

[2] Shanghai Jiao Tong Univ, State Key Lab Met Matrix Composite, Shanghai 200240, Peoples R China

来源：

ACTA MATERIALIA | 2016年 / 103卷

关键词：

Grain refinement; Nanoparticles; Modeling; Aluminum alloys; AL-SI ALLOYS; SOLUTE DIFFUSION-MODEL; SLIDING WEAR BEHAVIOR; GRAIN-REFINEMENT; DENDRITIC GROWTH; TI-B; SOLIDIFYING INTERFACES; TITANIUM CARBONITRIDE; PARTICLE ENGULFMENT; MATRIX COMPOSITES;

D O I：

10.1016/j.actamat.2015.10.005

中图分类号：

T [工业技术];

学科分类号：

08 ;

摘要：

In this study, significant grain refinement of Al-10Si alloys was achieved by rapid growth control induced by nanoparticles (NPs). Microstructure analysis revealed the three distribution types of nanoparticles in the matrix, i.e. intragranular distribution (within the interior of primary alpha-Al), intergranular distribution (along the grain boundary) and extragranular distribution (within the interior of eutectic structure), and the intergranular distribution is dominant in the matrix. During solidification, a great majority of nanoparticles distributed along grain boundaries can form a layer to restrict grain growth. An analytical model is proposed to predict the grain size of hypoeutectic Al-Si alloys, in which the final grain size can be related to the diffusion-hindrance efficiency of NPs that is proportional to the addition level and the time factor that is inversely proportional to the addition level. Model predictions demonstrate that with increasing NP additions, a more densely-packed nanolayer can be formed more rapidly, thus inhibiting the grain growth more efficiently. NP-induced growth control breaks the heavy barriers set by the inherent limitations of inoculation, and the model yields an insight into the understanding of the mechanism underlying NP-induced grain growth. (c) 2015 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

引用

页码：252 / 263

页数：12

共 50 条

[1] Effect of the addition of refiners and/or modifiers on the microstructure of die cast Al-12Si alloys [J].