Secondary recrystallization behavior in strip-cast grain-oriented silicon steel processed by isothermal secondary annealing
- State Key Laboratory of Rolling and Automation, Northeastern University, Shenyang 110819 (China)
- Laboratory for Excellence in Advanced Steel Research, Department of Metallurgical, Materials and Biomedical Engineering, University of Texas at EI Paso, EI Paso, TX 79912 (United States)
Highlights: • Abnormal grain growth was successfully developed after annealing at 1025 °C for 15 min. • The formation mechanism of the Goss and {110}<227> secondary grains was elucidated. • Retention of matrix grain colonies in the interior or at the grain boundaries of secondary grains was explained. - Abstract: The primary annealed sheets of strip-cast grain-oriented silicon steel were isothermally secondary annealed for 15 min under 100% H{sub 2} atmosphere. The microstructure and crystallographic orientation at different annealing temperatures were characterized and the secondary recrystallization behavior was elucidated. It was observed that relatively complete abnormal grain growth occurred at 1025 °C. Incomplete abnormal grain growth developed when the temperature was lower than 1025 °C, and normal grain growth occurred when the temperature was higher than 1025 °C. During the abnormal grain growth, both of the Goss and {110}<227> grains developed because of the rapid decrease of the inhibiting force and the limited annealing time. Considering the high energy boundary (HE), coincidence site lattice boundary (CSL) and solid-state wetting (SSW) models for abnormal grain growth, the first one explained the development of the Goss and {110}<227> grains. Another result was that several matrix grain colonies were observed in the interior or at the boundaries of secondary grains after abnormal grain growth. The grains at the periphery of these colonies showed a large fraction of high energy boundaries (20–45° misorientation) with the surrounding secondary grain and similar grain size with the unconsumed matrix grains. Therefore, these colonies were expected to be consumed by prolonging the annealing time and thus the limited annealing time was responsible for their occurrence. A possible explanation for the dominated high energy boundaries instead of low energy boundaries at the periphery of these colonies was proposed. All of these behaviors promoted the understanding of abnormal grain growth.
- OSTI ID:
- 22805074
- Journal Information:
- Materials Characterization, Vol. 142; Other Information: Copyright (c) 2017 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.; Country of input: International Atomic Energy Agency (IAEA); ISSN 1044-5803
- Country of Publication:
- United States
- Language:
- English
Similar Records
Coincidence site lattice (CSL) grain boundaries and Goss texture development in Fe-3% Si alloy
A role of fractions of mobile grain boundaries in secondary recrystallization of Fe-Si steels