Mechanism of competitive grain growth in directional solidification of a nickel-base superalloy

被引：187

作者：

Zhou, Y. Z. ^{[1
]}

Volek, A. ^{[2
]}

Green, N. R. ^{[1
]}

机构：

[1] Univ Birmingham, Sch Engn Met & Mat, Birmingham B15 2TT, W Midlands, England

[2] Diehl Stifung & Co KG, D-90478 Nurnberg, Germany

来源：

ACTA MATERIALIA | 2008年 / 56卷 / 11期

关键词：

grain growth; theory; directional solidification; nickel alloys;

D O I：

10.1016/j.actamat.2008.02.022

中图分类号：

T [工业技术];

学科分类号：

08 ;

摘要：

The structure evolution of bicrystal (BC) samples during directional solidification (DS) was explored in an attempt to understand the mechanism of competitive grain growth. It was found that in the case of diverging dendrites the favorably oriented grain overgrows the misaligned grain. However, in the case of converging dendrites the result differs from the prediction of the generally accepted model for competitive grain growth. First, the unfavorably oriented dendrites are able to overgrow the favorably oriented dendrites. Second, the misaligned grain overgrows the favorably oriented grain by blocking the dendrites of the favorably oriented grain at the grain boundary. Based on the experimental results, the process by which a favored [0 0 1] texture is developed during DS process of a nickel-base super-alloy is illustrated. (C) 2008 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

引用

页码：2631 / 2637

页数：7

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