@article{oai:u-ryukyu.repo.nii.ac.jp:02000818, author = {真壁, 朝敏 and Socie, Darrell F. and 末吉, 敏恭 and 上原, 崇 and Makabe, Chobin and Socie, Darrell F. and Sueyoshi, Toshiyasu and Uehara, Takashi}, issue = {689}, journal = {日本機械学会論文集. A編, Transactions of the Japan Society of Mechanical Engineers. A}, month = {Jan}, note = {The mechanism of shear mode fatigue crack growth in pure aluminum was investigated using pre-cracked specimen. The crack propagation tests were carried out by the cyclic torsion with a static axial load and the push-pull, respectively. In the case of the cyclic torsion, the fatigue crack grew by shear mode. The micro-cracks initiated perpendicular and parallel to the direction of main crack growth during the cyclic torsion. However, the interactions were not observed between the main crack and the micro-cracks, which directed perpendicular to the direction of main crack growth. The behavior of micro-cracks on pure aluminum was different from that of 4340 steel in which the pure shear mode crack growth hard to occurred. The crack growth behavior is related to the slip systems of the materials. The number of slip plane and the friction resistance between molecules of aluminum are smaller than those of steel. These and the loading conditions are related to the mechanism of the shear mode crack growth in aluminum. Under condition in the prenent study, the relation between the crack propagation rate and the stress intensity factor range was almost the same in the cases of the push-pull and the cyclic torsion with tension. However, the effects offriction between the crack surfaces on the crack propagation in a shear mode were not exactly evaluated., 論文}, pages = {84--92}, title = {純アルミニウムのせん断モード疲労き裂伝ぱ機構に関して}, volume = {70}, year = {2004} }