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Title: Estimation of Fatigue Damage for an Austenitic Stainless Steel (SUS304) Using Magnetic Methods

Abstract

There are some fatigue damage estimation methods of the austenitic stainless steel that uses the martensitic transformation. For instance, they are the remanent magnetization method, the excitation method, and so on. Those two methods are being researched also in our laboratory now. In the remanent magnetization method, it is well known that the relation between fatigue damage and the remanent magnetization is simple, clear, and reproducible. However, this method has the disadvantage to need a special magnetizer. This method cannot be easily used on the site such as the factory. On the other hand, because the special magnetizer is unnecessary, the excitation method can use easily on the site. The output signal of this method is small. In this paper, two fatigue evaluation methods such as the remanent magnetization method and the excitation method are introduced. In addition, we report on the result of comparing the fatigue evaluation performances of two methods.

Authors:
 [1];  [2]; ;  [3]
  1. Department of Computer and Control Engineering, Oita National College of Technology, 1666 Maki, Oita, 870-0152 (Japan)
  2. Department of Mechanical Engineering, Oita National College of Technology, 1666 Maki, Oita, 870-0152 (Japan)
  3. Department of Electrical and Electronic Engineering, Faculty of Engineering, Oita University, 700 Dannoharu, Oita, 870-1192 (Japan)
Publication Date:
OSTI Identifier:
21054943
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: 10.1063/1.2718114; (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; AUSTENITE; DAMAGE; EVALUATION; EXCITATION; FATIGUE; MAGNETIZATION; MARTENSITE; PERFORMANCE; PHASE TRANSFORMATIONS; STAINLESS STEEL-304; TESTING

Citation Formats

Oka, M., Yakushiji, T., Tsuchida, Y., and Enokizono, M. Estimation of Fatigue Damage for an Austenitic Stainless Steel (SUS304) Using Magnetic Methods. United States: N. p., 2007. Web. doi:10.1063/1.2718114.
Oka, M., Yakushiji, T., Tsuchida, Y., & Enokizono, M. Estimation of Fatigue Damage for an Austenitic Stainless Steel (SUS304) Using Magnetic Methods. United States. doi:10.1063/1.2718114.
Oka, M., Yakushiji, T., Tsuchida, Y., and Enokizono, M. Wed . "Estimation of Fatigue Damage for an Austenitic Stainless Steel (SUS304) Using Magnetic Methods". United States. doi:10.1063/1.2718114.
@article{osti_21054943,
title = {Estimation of Fatigue Damage for an Austenitic Stainless Steel (SUS304) Using Magnetic Methods},
author = {Oka, M. and Yakushiji, T. and Tsuchida, Y. and Enokizono, M.},
abstractNote = {There are some fatigue damage estimation methods of the austenitic stainless steel that uses the martensitic transformation. For instance, they are the remanent magnetization method, the excitation method, and so on. Those two methods are being researched also in our laboratory now. In the remanent magnetization method, it is well known that the relation between fatigue damage and the remanent magnetization is simple, clear, and reproducible. However, this method has the disadvantage to need a special magnetizer. This method cannot be easily used on the site such as the factory. On the other hand, because the special magnetizer is unnecessary, the excitation method can use easily on the site. The output signal of this method is small. In this paper, two fatigue evaluation methods such as the remanent magnetization method and the excitation method are introduced. In addition, we report on the result of comparing the fatigue evaluation performances of two methods.},
doi = {10.1063/1.2718114},
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}
}
  • The interrupted low cycle fatigue test of austenitic stainless steel was conducted and the dislocation structure and fatigue damage was evaluated subsequently by using both transmission electron microscope and nonlinear ultrasonic wave techniques. A “mountain shape” correlation between the nonlinear acoustic parameter and the fatigue life fraction was achieved. This was ascribed to the generation and evolution of planar dislocation structure and nonplanar dislocation structure such as veins, walls, and cells. The “mountain shape” correlation was interpreted successfully by the combined contribution of dislocation monopole and dipole with an internal-stress dependent term of acoustic nonlinearity.
  • Austenitic stainless steel transforms from austenitic crystal structure to martensitic crystal structure after applying strain or stress. Because martensitic crystal structures have magnetization, strain evaluation and fatigue evaluation can be performed by measuring magnetic properties. This paper describes the measurement of leakage magnetic flux density of remanent magnetization for the strain evaluation and the fatigue evaluation by a typical Hall element sensor for SUS 304 and SUS 304L and by a high-sensitivity thin-film flux-gate magnetic sensor for SUS 316 and SUS 316L.
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