REPO

Memoirs of the Faculty of Engineering, Okayama University 30巻 2号
1996-03-29 発行

Nature of Brittle Fracture in Aged Ti-Mo Alloy

竹元 嘉利 Department of Mechanichal Engineering Kaken ID publons researchmap
飛田 守孝 Department of Mechanichal Engineering
榊原 精 Department of Mechanichal Engineering
Publication Date
1996-03-29
Abstract
The mechanism of brittle fracture in Ti-14mass % Mo alloy aged for 1x10(6)s at 623K was studied using transmission electron microscopy (TEM) and dynamic hardness test (DHT) on the structure deformed by means of tensile elongation at elevated temperature or cold rolling. Many band products were observed by TEM in either deformed specimens. These band products were identified to neither slips nor twinning bands, moreover, they were different from α , α ' and α " phases. The band product consisted of β phase and granular unknown phase which was transformed by deformation from ω phase. The newly discovered phase, named β" phase, in the band products had a body-centered triclinic structure. The β" was similar to the ω zone with respect to the morphology and the concentration of Mo, but it resembled β in structure. The result of DHT on the band products and the matrix showed that the band products were softer than the matrix. It is suggested that the band products are easily deformed because of the disappearance of obstacles such as ω phase, and consequently behave like paths to lead cracks preferentially.
ISSN
0475-0071
NCID
AA10699856
NAID