Grant-in-Aid for Scientific Research (C)
|Allocation Type||Single-year Grants|
|Research Institution||Osaka University|
MURAKAWA Hidekazu Joining and Welding Research Institute, Osaka Univ. Associate Professor, 接合科学研究所, 助教授 (60166270)
OSAWA Naoki Graduate School of Engineering, Osaka Univ. Associate Professor, 大学院・工学研究科, 助教授 (90252585)
|Project Period (FY)
1997 – 1999
Completed(Fiscal Year 1999)
|Budget Amount *help
¥3,100,000 (Direct Cost : ¥3,100,000)
Fiscal Year 1999 : ¥700,000 (Direct Cost : ¥700,000)
Fiscal Year 1998 : ¥700,000 (Direct Cost : ¥700,000)
Fiscal Year 1997 : ¥1,700,000 (Direct Cost : ¥1,700,000)
|Keywords||Energy Release Rate / Crack Propagation / Finite Element Method / Interface Element / Delamination / Ductile Crack / Dynamic Crack Propagation / Crack Propagation Speed / 非線形数値破壊力学 / 界面ポテンシャル / 動的き裂伝播 / き裂伝播速度 / シャルピー衝撃試験 / 延性破壊 / 強度評価|
In the present research, the energy release rate is selected as a basic concept to understand the crack propagation problem since it has clear physical meaning. To compute the G-value, full advantage of nonlinear FEM, which considers finite strain plasticity, is taken. Also, FEM introducing an interface element is developed specially for the crack propagation analysis. The proposed method is applied to various problems listed below and its potential usefulness is demonstrated.
The interface element models the formation of new surfaces during the crack propagation. Such interface elements are arranged along the crack propagation path so that the analysis of the crack propagating with dissipating the energy equal to the surface energy.
(1) Developed programs
Program to compute G-value for axisymmetric elastic large deformation problem.
Program to compute G-value for 3-dimensional finite-strain-elastic-plastic problem
Programs for static and dynamic crack propagation using interface element (2-dimensional and 3-dimensional finite-strain-elastic-plastic problems)
Programs for static and dynamic crack propagation using interface element
Program for hot cracking using temperature dependent interface element
(2) Investigated problems
Debonding of thin film on substrate accompanying buckling.
Effect of Strain Hardening Properties of Material on Toughness
Analysis of Delamination between bonded plates
Steady Ductile Crack Propagation in Center Notched Steel Plate
Influence of inertia force on Charpy Impact Test
Influence of Applied Stress on Speed of Dynamically Propagating Crack in Elastic Plate
Influence of Specimen Geometry and Welding Conditions of Hot Cracking in Weld