@article{oai:jaxa.repo.nii.ac.jp:00031667,
 author = {斎藤, 敏 and 岸, 輝雄 and 堀内, 良 and 中之瀬, 恩 and 垣見, 恒男 and SAITO, S. and KISHI, T. and HORIUCHI, R. and NAKANOSE, M. and KAKIMI, T.},
 issue = {1_A},
 journal = {東京大学宇宙航空研究所報告},
 month = {Feb},
 note = {Acoustic emission technique was applied to fracture toughness testing in Ti-6Al-4V alloys to detect crack growth. The results are as follows: (1) From the analysis of acoustic emission signals, two characteristic points (A and B points) were found. The first A-point corresponds to the initiation of slow crack growth, and the second B-point the initial deviation of crack opening displacement. These results were also verified by the observation with microscope and crack gauge. (2) The load of A-point was almost 60%of maximum load and that of B-point was 80-90%, while the load of K_<IC> value was 93-95% of maximum load. These results suggest that acoustic emission technique is a most sensitive one to detect slow crack growth. (3) There exists planer anisotropy in this alloy. J_<IC> value defined by A point had the anisotropy, which corresponds to the inclination of COD_<crit>, but not to that of K_<IC>., 資料番号: SA0124661000},
 pages = {227--240},
 title = {球形ロケットチャンバ用チタン合金の破壊靭性値とAcoustic Emission},
 volume = {12},
 year = {1976}
}