九州大学 · 工学
東田博之教授の研究室では、シンクロトロンX線マイクロトモグラフィーを活用した材料内部の3次元微細構造観察を柱として、疲労割れ、応力腐食割れ、水素脆化、微小空孔の成長挙動など、材料の破壊挙動を高分解能で可視化・定量する研究を進めています。特に、TEMに代わるナノスケールの内部構造観察や、応力・ひずみ場の3次元マッピング技術の開発が特色です。実験的・計測的アプローチに加え、材料の破壊機構解明に貢献する革新的な画像解析手法の構築が目指されています。
Figures are computed from collected data and may differ slightly.
Synchrotron X-ray microtomography has been utilized for the in-situ observation of steady-state plane-strain fatigue crack growth. A high-resolution experimental configuration and phase contrast imaging technique have enabled the reconstruction of crack images with an isotropic voxel with a 0.7 µm edge. The details of a crack are readily observed, together with evidence of the incidence and mechanical influence of closure. After preliminary investigations of the achievable accuracy and reproduci
The single-distance phase retrieval technique was applied to contrast-enhanced imaging of the dual-phase microstructure of a ferrite/martensite dual-phase with only 1.4% difference in density between the two phases. Each high-resolution absorption-contrast image was registered with a corresponding phase-contrast image, to analyse damage evolution behaviour. The loading step at which each microvoid was nucleated was identified by tracking the microvoid throughout tension, together with its nuclea
Al-10Mg alloys, which are highly susceptible to SCC, were prepared with various β precipitate morphologies. Interrupted in-situ tensile tests were conducted under synchrotron X-ray radiation, employing a recently developed X-ray microtomography technique that combines high-energy, applicability to metallic materials, and ultra-high resolution. Preferential dissolution of the β phase along grain boundaries, and incidental intergranular and transgranular fracture, were observed in 3D. A drastic de
Microtomography combined with hard x-ray imaging microscopy has been employed to observe nanoscopic features in a material, which has, to date, only been done by the transmission electron microscopy (TEM). Here, the authors show a characteristic microstructure in an aluminum alloy, such as a slant gap between growing precipitates that impinge on each other due to the presence of a solute-depleted zone. Such observation is not possible by conventional projection microtomography even using the hig
Open papers in the app to read, cite, and organize with AI.