Study of computerized tomography and strain mapping in the vicinity of crack tip in steel material using synchrotron white X-ray

放射光白色X線を用いた鉄鋼材領内のき裂先端のCT観察及びひずみマッピングに関する研究

柴野 純一*; 梶原 堅太郎*; 桐山 幸治; 菖蒲 敬久  ; 鈴木 賢治*; 新居 恭征*; 三浦 節男*; 小林 道明*

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

A computerized tomography and a strain mapping in the vicinity of a crack tip in steel were investigated using a high energy white X-ray obtained from BL28B2 beam line at SPring-8 in Japan. Low-alloy and high-tensile steel (JIS G3128 SHY685) was used as a specimen prepared in the cylindrical geometry. A fatigue crack was introduced into the specimen by a cyclic loading. As the results, the computerized tomography of the crack in the specimen under the loading of crack opening was practicable by using the synchrotron white X-ray. The contour map of the internal strain near the crack tip of the steel of 5mm diameter could be obtained using the white X-ray with energy ranging from 50keV to 150keV. It was confirmed that the synchrotron white X-ray is useful for the computerized tomography of the internal crack and the strain mapping near it.