異方性を有する純チタン膜材の疲労き裂進展に伴う作動すべり系の推定

（EBSD法による結晶方位測定に基づいて）

抄録

Using a fatigue testing method by which fatigue cracks can be initiated and propagated in a film adhered to cover an circular through-hole in a base plate subjected to cyclic loads, annealed rolled commercially-pure titanium films with Anisotropy of 30μm thickness were fatigued under constant stress amplitudes with a stress ratio of R=0. In order to discuss correlation between fatigue crack propagation and change of crystal orientation, crystal orientation on the surface of the film materials was measured before and after fatigue testing. The crystallographic information of these films was analyzed using the Electron Back-scatter Diffraction (EBSD) system. As a result, fatigue cracks propagated faster in the specimen loaded to the rolling direction than in that loaded to the transverse direction. It is considered that the fatigue crack propagated by prismatic slips with screw dislocations in the specimen loaded to the rolling direction. On the other hand, the fatigue crack seems to propagate by basal slips with edge dislocations in the specimen loaded to the transverse direction.