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Title: Development of a System to Measure Recrystallization Ratio of Plate Steel Using Laser-Based Ultrasonics

Abstract

In this study, a material property measurement system of plate steel using laser-based ultrasonics has been developed. The system consists of pulsed Nd:YAG laser for ultrasonic generation, CW single frequency laser and Fabry-Perot interferometer for ultrasonic detection. The system generates and detects shear waves and precisely calculates anisotropy parameter values of shear wave velocities of test samples. At first, the relationship between anisotropy parameter and recrystallization ratio was investigated in the laboratory experiments. Quenching the test samples just after the ultrasonic measurement, recrystallization ratio values were measured by the conventional microscopic method. According to the experimental results, the anisotropy parameter values showed a good correlation with actual recrystallization ratio values. To evaluate the applicability of the system to real steel production line, the system was installed in hot rolling pilot plant of plate steel. As the results, it was demonstrated that the system could measure the recrystallization ratio using the anisotropy parameter values of shear wave velocities, even in the environment of hot rolling pilot plant.

Authors:
; ;  [1]; ; ; ; ;  [2]
  1. Environment and Process Technology Center, Nippon Steel Corporation, Futtu-shi, Chiba (Japan)
  2. POSLAB, POSCO, Pohang, Gyeongbuk (Korea, Republic of)
Publication Date:
OSTI Identifier:
21054952
Resource Type:
Journal Article
Resource Relation:
Journal Name: AIP Conference Proceedings; Journal Volume: 894; Journal Issue: 1; Conference: Conference on review of progress in quantitative nondestructive evaluation, Portland, OR (United States), 30 Jul - 4 Aug 2006; Other Information: DOI: 10.1063/1.2718166; (c) 2007 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; ANISOTROPY; CORRELATIONS; DETECTION; FABRY-PEROT INTERFEROMETER; MEASURING METHODS; NEODYMIUM LASERS; PILOT PLANTS; PLATES; RECRYSTALLIZATION; ROLLING; SHEAR; STEELS; ULTRASONIC TESTING; ULTRASONIC WAVES; VELOCITY

Citation Formats

Nagata, Y., Yamada, H., Hamada, N., Lim, C. S., Yi, J. K., Hong, S. T., Choi, S. G., and Oh, K. J.. Development of a System to Measure Recrystallization Ratio of Plate Steel Using Laser-Based Ultrasonics. United States: N. p., 2007. Web. doi:10.1063/1.2718166.
Nagata, Y., Yamada, H., Hamada, N., Lim, C. S., Yi, J. K., Hong, S. T., Choi, S. G., & Oh, K. J.. Development of a System to Measure Recrystallization Ratio of Plate Steel Using Laser-Based Ultrasonics. United States. doi:10.1063/1.2718166.
Nagata, Y., Yamada, H., Hamada, N., Lim, C. S., Yi, J. K., Hong, S. T., Choi, S. G., and Oh, K. J.. Wed . "Development of a System to Measure Recrystallization Ratio of Plate Steel Using Laser-Based Ultrasonics". United States. doi:10.1063/1.2718166.
@article{osti_21054952,
title = {Development of a System to Measure Recrystallization Ratio of Plate Steel Using Laser-Based Ultrasonics},
author = {Nagata, Y. and Yamada, H. and Hamada, N. and Lim, C. S. and Yi, J. K. and Hong, S. T. and Choi, S. G. and Oh, K. J.},
abstractNote = {In this study, a material property measurement system of plate steel using laser-based ultrasonics has been developed. The system consists of pulsed Nd:YAG laser for ultrasonic generation, CW single frequency laser and Fabry-Perot interferometer for ultrasonic detection. The system generates and detects shear waves and precisely calculates anisotropy parameter values of shear wave velocities of test samples. At first, the relationship between anisotropy parameter and recrystallization ratio was investigated in the laboratory experiments. Quenching the test samples just after the ultrasonic measurement, recrystallization ratio values were measured by the conventional microscopic method. According to the experimental results, the anisotropy parameter values showed a good correlation with actual recrystallization ratio values. To evaluate the applicability of the system to real steel production line, the system was installed in hot rolling pilot plant of plate steel. As the results, it was demonstrated that the system could measure the recrystallization ratio using the anisotropy parameter values of shear wave velocities, even in the environment of hot rolling pilot plant.},
doi = {10.1063/1.2718166},
journal = {AIP Conference Proceedings},
number = 1,
volume = 894,
place = {United States},
year = {Wed Mar 21 00:00:00 EDT 2007},
month = {Wed Mar 21 00:00:00 EDT 2007}
}
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