Evaluation of ductile damage in aluminum single crystal with prior activity of single slip system under tensile loading

Shibano, Junichi*; Kajiwara, Kentaro*; Tsukamoto, Takuya*; Kawai, Hirokazu*; Miura, Setsuo*; Zhang, S.*; Shobu, Takahisa

Zairyo, 63(7), p.533 - 538, 2014/07

https://doi.org/10.2472/jsms.63.533

A ductile damage progress of an aluminum single crystal with the prior activity of the single slip system under tensile loading was verified by a profile analysis using white X-ray obtained in BL28B2 beam line of SPring-8. In profile analysis, an instrumental function was defined in consideration both of a divergence by slits and a response function peculiar to the energy dispersive method. As a result, dislocation density increased as ductile damage progressed, but it was relatively low near the notch. The influence of a release of the strain energy by a ductile damage progress was expected. The characteristics of ductile damage progress near the notch of the aluminum single crystal with a prior activity of a single slip system under the tensile loading were clarified from the distribution of dislocation density.

Study on evaluation of ductile damage of aluminum single crystal using synchrotron white X-ray

Shibano, Junichi*; Kiso, Minoru*; Kajiwara, Kentaro*; Shobu, Takahisa; Miura, Setsuo*; Kobayashi, Michiaki*

Zairyo, 62(7), p.443 - 450, 2013/07

https://doi.org/10.2472/jsms.62.443

The ductile damage progress of the FCC single crystal was verified by the profile analysis using the white X-ray obtained in BL28B2 beam-line of SPring-8. In this study, an aluminum single crystal of the purity 6N was used as a specimen prepared in the I-type geometry for tensile test. The notch was introduced into one side of the center of a parallel part of the specimen by wire electric discharge machining. White X-ray, which has 200 microns in height and 100 microns in width, was incident into the specimen on the Bragg angle of 3 in the horizontal plane using energy dispersive X-ray diffraction technique. As a result, in 1.1% of applied strain, increase of the lattice strain was observed in the direction of about 45 of slant from the notch bottom. In 2.2% of applied strain, the lattice strain reduced in the direction of about 45 of slant from the notch bottom. Non-uniform strain and dislocation density decreased similarly.

New developments of materials evaluation by diffraction method, 2; Stress measurement by high energy X-rays using synchrotron radiation

Shobu, Takahisa; Shibano, Junichi*

Zairyo, 58(11), p.948 - 954, 2009/11

https://doi.org/10.2472/jsms.58.948

no abstracts in English

Study on imaging and strain mapping in the vicinity of internal crack tip using synchrotron white X-ray

Shibano, Junichi*; Kajiwara, Kentaro*; Kiriyama, Koji; Shobu, Takahisa; Suzuki, Kenji*; Nishimura, Suguru*; Miura, Setsuo*; Kobayashi, Michiaki*

Zairyo, 57(7), p.667 - 673, 2008/07

https://doi.org/10.2472/jsms.57.667

Measurement of internal strain in materials using high energy synchrotron radiation white X-rays

Shibano, Junichi*; Shobu, Takahisa; Suzuki, Kenji*; Hirata, Tomoyuki*; Kaneko, Hiroshi; Kobayashi, Michiaki*

Zairyo, 56(10), p.985 - 992, 2007/10

https://doi.org/10.2472/jsms.56.985

This paper presents a basic research on a measurement of strain in the bulk of materials by using high energy white X-rays from a synchrotron radiation source of SPring-8. WEL-TEN780E (JIS G3128 SHY685) whose grain size was 0.013 mm was used as a specimen. The specimen was loaded with four point bending. The white X-ray beam, which has a height of 0.05 mm and width of 0.03 mm, was incident in it. Bending strain at the surface of specimen was measured by a strain gauge. The internal strain of SHY685 of 5 mm thickness could be evaluated using white X-rays which range of energy from 60 keV to 150 keV. Furthermore, the measurement error of strain could be decreased by using the diffracted X-rays with high energy, high peak count and the profile which is close to Gaussian curve. The results showed that the high energy white X-ray is effective for internal strain measurements.

Strain measurement of multi-phase steel using SR white X-ray

Kiriyama, Koji; Shobu, Takahisa; Shibano, Junichi*; Kaneko, Hiroshi

no journal, , 

In the case of strain (or stress) measurement of multi-phase steel, many reflection data will be need to analyze strain because of considering with each strain of phase. On the other hand, strain measurement method using SR white X-ray are effective to get many reflection by using energy-dispersive X-ray spectroscopy. In this study, strain measurement of duplex stainless steel was done. The results show that the method has no problem to be applied to strain measure of duplex stainless steel, and that correlation between measured strain and elastic constants of reflection face.

Strain measurement and computed tomography of cracking zone in steel material by high energy white synchrotron radiation

Kiriyama, Koji; Shibano, Junichi*; Kajiwara, Kentaro*; Shobu, Takahisa; Suzuki, Kenji*; Kaneko, Hiroshi; Nishimura, Suguru*; Arai, Takayuki*

no journal, , 

Residual stress measurement is important to understand SCC (Stress Corrosion Cracking) process. In this study, CT (Computed Tomography) imaging and inner strain mapping of steel material (alpha-Fe) have performed at BL28B2 at SPring-8. The result showed that artificial cracking in the sample was clearly measured by CT and that strain maps quite correspond to CT image. Therefore, these methods are very effective tool to measure an inner state of steel material.

Inner strain measurement of duplex stainless steel using by SR white X-ray

Kiriyama, Koji; Shobu, Takahisa; Shibano, Junichi*; Kaneko, Hiroshi

no journal, , 

Inner strain measurement of duplex stainless steel, many reflection data will be need to analyze strain because of considering with each strain of phase. Therefore, strain measurement method using SR white X-ray are effective to get many reflection by using energy-dispersive X-ray spectroscopy. The results show that the method is suitable to be applied to strain measure of duplex stainless steel, and that correlation between measured strain and elastic constants of reflection face.

Measurement of stress and imaging in the vicinity of fatigue crack in steel material using synchrotron radiation white X-rays

Kiriyama, Koji; Shibano, Junichi*; Kajiwara, Kentaro*; Shobu, Takahisa; Suzuki, Kenji*; Kaneko, Hiroshi; Nishimura, Suguru*; Arai, Takayuki*; Miura, Setsuo*; Kobayashi, Michiaki*

no journal, , 

Residual stress measurement is important to understand Stress Corrosion Cracking process. In this study, measurements of imaging and inner stress mapping around a crack-tip in steel material (alpha-Fe) have performed at beam-line BL14B1 and BL28B2 at SPring-8. The results showed that artificial cracking in the sample was clearly measured by imaging and that stress maps quite correspond to the result of imaging. Therefore, these methods are very effective tool for measurement of inner state of steel material.

Evaluation of dislocation density in tensile rapture specimen

Shobu, Takahisa; Yasuda, Ryo*; Shiro, Ayumi*; Yoshida, Yutaka*; Tokuda, Susumu*; Shibano, Junichi*; Kumagai, Masayoshi*

no journal, , 

A dislocation density increases and fatigue failure of the structure occur, when a metal is deformed. In this study, dislocation density of a broken 0.3 mm thick SUS316L specimen was calculated by line profile analysis obtained by high energy synchrotron X-ray diffraction method, and a relationship between fatigue fracture and dislocation density was evaluated. As a result of the analysis, it was revealed that the dislocation density abruptly increases as approaching the fracture part. In addition, it was revealed that the bcc structure appeared in the fcc structure which is the basic structure in the fracture part. In steel, the increase in dislocation density is closely related to the increase in material strength, and the material strength of steel with bcc structure is known to be higher than that with fcc structure. So, it seems that the structure has changed due to a sharp increase in dislocation density at the fracture part.