Suppression of Coarse Columnar Grain Formation in As-cast Austenite Structure of a Hyperperitectic Carbon Steel by Nb Addition

被引：10

作者：

Ohno, Munekazu ^{[1
]}

Yamaguchi, Tetsuya ^{[2
]}

Matsuura, Kiyotaka ^{[1
]}

Isobe, Kohichi ^{[3
]}

机构：

[1] Hokkaido Univ, Div Mat Sci & Engn, Fac Engn, Kita Ku, Sapporo, Hokkaido 0608628, Japan

[2] Hokkaido Univ, Grad Sch Engn, Sapporo, Hokkaido 0608628, Japan

[3] Nippon Steel Corp Ltd, Muroran R&D Lab, Muroran, Hokkaido 0508850, Japan

来源：

ISIJ INTERNATIONAL | 2011年 / 51卷 / 11期

关键词：

solidification; casting; peritectic steel; pinning; grain refinement; austenite grain structure; columnar grain; HOT-DUCTILITY; GROWTH; AL; SOLIDIFICATION;

D O I：

10.2355/isijinternational.51.1831

中图分类号：

TF [冶金工业];

学科分类号：

0806 ;

摘要：

Effects of Nb addition on as-cast gamma-austenite grain structure in 0.2 mass% carbon steel are investigated by means of furnace cooling and permanent mold casting experiments. In the furnace-cooled samples with Nb addition, Nb(C,N) particles crystallize from the last-solidifying liquid in non-equilibrium solidification condition and they act as pinning particles for gamma grain growth just after the solidification completion. The Nb addition produces a strong pinning effect on the as-cast gamma grain structure. In the permanent mold casting experiment, Coarse Columnar Grains (CCG) structure develops from the mold wall in the sample without Nb. The increase in Nb concentration gradually decreases the fraction of CCG region and increases the fraction of Fine Columnar Grains (FCG), thus leading to the grain refinement. This refinement could be ascribed to the pinning effect of Nb(C,N) particles.

引用

页码：1831 / 1837

页数：7

共 21 条

[1] Nonisothermal Austenite Grain Growth Kinetics in a Microalloyed X80 Linepipe Steel [J].