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Directional recrystallization and microstructures of an Fe–6.5wt%Si alloy

Published online by Cambridge University Press:  31 January 2011

Zhongwu Zhang
Affiliation:
Engineering Research Center of Materials Behavior and Design, Ministry of Education, Nanjing University of Science and Technology, Nanjing 210094, People’s Republic of China
Guang Chen*
Affiliation:
Engineering Research Center of Materials Behavior and Design, Ministry of Education, Nanjing University of Science and Technology, Nanjing 210094, People’s Republic of China; and Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831
Hongbin Bei*
Affiliation:
Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831
Feng Li
Affiliation:
Engineering Research Center of Materials Behavior and Design, Ministry of Education, Nanjing University of Science and Technology, Nanjing 210094, People’s Republic of China
Feng Ye
Affiliation:
State Key Laboratory for Advanced Metals and Materials, USTB, Beijing 100083, People’s Republic of China
G.L. Chen
Affiliation:
Engineering Research Center of Materials Behavior and Design, Ministry of Education, Nanjing University of Science and Technology, Nanjing 210094, People’s Republic of China; and State Key Laboratory for Advanced Metals and Materials, USTB, Beijing 100083, People’s Republic of China
C.T. Liu
Affiliation:
Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831; and Mechanical Engineering Department, Hong Kong Polytechnic University, Hong Kong
*
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Abstract

Directional recrystallization of an Fe–6.5wt%Si alloy was investigated by changing hot zone temperatures and growth rates. Elongated (columnar) grains with an aspect ratio more than 10 can be produced when growth parameters are carefully adjusted. It was found that at a fixed growth rate, the grain length and aspect ratio increase with increased hot zone temperatures. At a fixed hot zone temperature, there is a critical growth rate at which columnar grains have the largest average aspect ratio. Below or above this growth rate, the aspect ratio decreases. Texture and grain orientation analysis showed that the preferentially selective growth to form columnar grains was favored by the formation of low-energy surfaces and grain boundaries.

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Articles
Copyright
Copyright © Materials Research Society 2009

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