Fracture behavior and deformation capacity of welded joint in high-speed tensile tests
Project/Area Number |
17560506
|
Research Category |
Grant-in-Aid for Scientific Research (C)
|
Allocation Type | Single-year Grants |
Section | 一般 |
Research Field |
Building structures/materials
|
Research Institution | Osaka University |
Principal Investigator |
SAKINO Yoshihiro Osaka University, Joining and welding research institute, Assist. Prof. (80273712)
|
Project Period (FY) |
2005 – 2006
|
Project Status |
Completed (Fiscal Year 2006)
|
Budget Amount *help |
¥3,600,000 (Direct Cost: ¥3,600,000)
Fiscal Year 2006: ¥1,500,000 (Direct Cost: ¥1,500,000)
Fiscal Year 2005: ¥2,100,000 (Direct Cost: ¥2,100,000)
|
Keywords | High-speed tensile test / Strain-rate / Simulated HAZ test / Charpy absorbed energy / Welding heat input / Deformation capasity / Aging / High-strength steel |
Research Abstract |
Many steel structures were damaged by recent earthquake. It can be considered that effect of strain rate is one of the substantial factors of these damages. But the effect of strain rate was elucidated only on virgin steel. Generally, steel structure is damaged in weld zone. Moreover, it is also well known that the cold forming and aging makes steels also brittle. In this study, experiments were carried out in order to elucidate the effect of strain rate on tensile properties of the weld heat-affected zone. Moreover, the effect of strain rate of aged and heat-affected area. In the experiment, the heat-affected zone and aged zone simulated on tensile specimen, and the tensile test under 3 tensile speeds (0.1mm/s, 100mm/s, 1200mm/s) was carried with those specimens. The main results are summarized as follows. ・ In case of the small Charpy absorbed energy specimen, crystallinity became large as the tensile speed increase. ・Tensile strength of ductile-fractured specimen became large as the tensile speed increase, even in the weld heat-affected steel and aged steel. And it is elucidate that the increase-ratio of tensile strength by increasing of tensile speed related well to the tensile strength under static loading. But tensile strength of brittle-fractured specimen does not increase if the tensile speed increase. ・In case of the no stress concentration specimen, deformation capacity became small as the tensile speed increase. ・In case of the notched specimen, deformation capacity of large Charpy absorbed energy specimen became large as the tensile speed increase, even in the weld heat-affected steel and aged steel. But deformation capacity of small Charpy absorbed energy specimen became decrease greatly as the tensile speed increase. Thus, it is elucidate that the change of deformation capacity is affected well by the Charpy absorbed energy.
|
Report
(4 results)
Research Products
(20 results)