The Experts below are selected from a list of 9954 Experts worldwide ranked by ideXlab platform
Hideki Yuya - One of the best experts on this subject based on the ideXlab platform.
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investigation of electromagnetic nondestructive evaluation of residual strain in Low Carbon Steels using the eddy current magnetic signature ec ms method
2019Co-Authors: Takanori Matsumoto, Shinji Oozono, Gerd Dobmann, Benjamin Ducharne, Tetsuya Uchimoto, Toshiyuki Takagi, Hideki YuyaAbstract:Abstract A novel magnetic nondestructive testing method, that is named eddy current magnetic signature (EC-MS) method, is proposed to evaluate the residual strain in Low Carbon Steels. This method relies on characterization of eddy current signals in the impedance plane if Low frequency major magnetization is superimposed. To investigate the mechanism of the proposed method, the eddy current magnetic signatures of a set of tensile test specimens are measured, and their relationship to the residual strain is surveyed. The trajectories of the eddy current signals show significant dependences on the residual strain; the EC-MS changes depending on the three residual strain stages, the region just after elastic limit before yield point, the Luders-strain region, and the region after start of work hardening. The EC-MS under elastic strain/stress is measured to investigate the influence of stress on the EC-MS. Numerical calculation is performed considering micro-eddy current field associated with moving domain walls and compared with experimental results to interpret the EC-MS phenomena.
Dong Hyuk Shin - One of the best experts on this subject based on the ideXlab platform.
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microstructural development of adiabatic shear bands in ultra fine grained Low Carbon Steels fabricated by equal channel angular pressing
2006Co-Authors: Byoungchul Hwang, Sunghak Lee, Yong Chan Kim, Nack J Kim, Dong Hyuk ShinAbstract:Abstract Microstructural development of adiabatic shear bands formed in ultra-fine-grained Low-Carbon Steels fabricated by equal channel angular pressing (ECAP) was investigated in this study. Dynamic torsional tests were conducted on four steel specimens, two of which were annealed after ECAP, using a torsional Kolsky bar. The ECAP’ed specimen consisted of fine equiaxed grains of 0.2 μm in size, which were slightly coarsened and had an equiaxed shape after annealing. Some adiabatic shear bands were observed at the gage center of the dynamically deformed torsional specimen, and their width was narrower in the ECAP’ed specimen than in the 1-h annealed specimen. Detailed transmission electron microscopic analysis on adiabatic shear bands indicated that very fine equiaxed grains of 0.05–0.2 μm in size were developed within the adiabatic shear band, and that cell structures were formed in the shear band flank by partitioning elongated ferrites. These phenomena were explained by dynamic recovery and recrystallization due to the highly localized plastic deformation and temperature rise occurring in the shear band. The temperature rise in the shear band formation process was estimated to be above 540 °C by observing spheroidized cementites inside pearlite grains.
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formation of fine cementite precipitates by static annealing of equal channel angular pressed Low Carbon Steels
2001Co-Authors: Dong Hyuk Shin, Yongseog Kim, E J LaverniaAbstract:Abstract In this study, a static annealing of Low-Carbon Steels severely deformed by equal-channel angular pressing was conducted. Employment of the processing route on a Low-Carbon steel containing 0.06% vanadium resulted in the formation of cementite precipitations as well as the refinement of ferrite grains to submicrometer size. During the static annealing treatment, rod-like cementites in the pearlite colonies of the sample decomposed to form spherical cementite precipitates distributed uniformly in ferrite grains. The decomposition phenomenon of the cementite is discussed on the basis of the dislocation–cementite interaction.
Takanori Matsumoto - One of the best experts on this subject based on the ideXlab platform.
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investigation of electromagnetic nondestructive evaluation of residual strain in Low Carbon Steels using the eddy current magnetic signature ec ms method
2019Co-Authors: Takanori Matsumoto, Shinji Oozono, Gerd Dobmann, Benjamin Ducharne, Tetsuya Uchimoto, Toshiyuki Takagi, Hideki YuyaAbstract:Abstract A novel magnetic nondestructive testing method, that is named eddy current magnetic signature (EC-MS) method, is proposed to evaluate the residual strain in Low Carbon Steels. This method relies on characterization of eddy current signals in the impedance plane if Low frequency major magnetization is superimposed. To investigate the mechanism of the proposed method, the eddy current magnetic signatures of a set of tensile test specimens are measured, and their relationship to the residual strain is surveyed. The trajectories of the eddy current signals show significant dependences on the residual strain; the EC-MS changes depending on the three residual strain stages, the region just after elastic limit before yield point, the Luders-strain region, and the region after start of work hardening. The EC-MS under elastic strain/stress is measured to investigate the influence of stress on the EC-MS. Numerical calculation is performed considering micro-eddy current field associated with moving domain walls and compared with experimental results to interpret the EC-MS phenomena.
Gerd Dobmann - One of the best experts on this subject based on the ideXlab platform.
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investigation of electromagnetic nondestructive evaluation of residual strain in Low Carbon Steels using the eddy current magnetic signature ec ms method
2019Co-Authors: Takanori Matsumoto, Shinji Oozono, Gerd Dobmann, Benjamin Ducharne, Tetsuya Uchimoto, Toshiyuki Takagi, Hideki YuyaAbstract:Abstract A novel magnetic nondestructive testing method, that is named eddy current magnetic signature (EC-MS) method, is proposed to evaluate the residual strain in Low Carbon Steels. This method relies on characterization of eddy current signals in the impedance plane if Low frequency major magnetization is superimposed. To investigate the mechanism of the proposed method, the eddy current magnetic signatures of a set of tensile test specimens are measured, and their relationship to the residual strain is surveyed. The trajectories of the eddy current signals show significant dependences on the residual strain; the EC-MS changes depending on the three residual strain stages, the region just after elastic limit before yield point, the Luders-strain region, and the region after start of work hardening. The EC-MS under elastic strain/stress is measured to investigate the influence of stress on the EC-MS. Numerical calculation is performed considering micro-eddy current field associated with moving domain walls and compared with experimental results to interpret the EC-MS phenomena.
Tetsuya Uchimoto - One of the best experts on this subject based on the ideXlab platform.
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investigation of electromagnetic nondestructive evaluation of residual strain in Low Carbon Steels using the eddy current magnetic signature ec ms method
2019Co-Authors: Takanori Matsumoto, Shinji Oozono, Gerd Dobmann, Benjamin Ducharne, Tetsuya Uchimoto, Toshiyuki Takagi, Hideki YuyaAbstract:Abstract A novel magnetic nondestructive testing method, that is named eddy current magnetic signature (EC-MS) method, is proposed to evaluate the residual strain in Low Carbon Steels. This method relies on characterization of eddy current signals in the impedance plane if Low frequency major magnetization is superimposed. To investigate the mechanism of the proposed method, the eddy current magnetic signatures of a set of tensile test specimens are measured, and their relationship to the residual strain is surveyed. The trajectories of the eddy current signals show significant dependences on the residual strain; the EC-MS changes depending on the three residual strain stages, the region just after elastic limit before yield point, the Luders-strain region, and the region after start of work hardening. The EC-MS under elastic strain/stress is measured to investigate the influence of stress on the EC-MS. Numerical calculation is performed considering micro-eddy current field associated with moving domain walls and compared with experimental results to interpret the EC-MS phenomena.
