The unified model of fatigue crack growth from micro- to macro-scale and its engineering application
In the past work, Sih and Tang have developed a multi-scale crack model based on the concept of restraining stress zone. This physically-based model has the ability to describe the whole fatigue process from micro- to macro-scale in a consistent way. By taking the dual scale strain energy density factor as the controlling quantity, the formulation for the fatigue crack growth from micro to macro is developed. Three basic parameters of material microstructure are involved in the formulation, say micro/macro shear modulus ratio μ*, the restraining stress ratio σ* and characteristic length ratio d*. By using this model, the fatigue test data for the plate specimens of aluminum alloy LY12 can be exactly re-produced. It shows that when the microscopic effects are taken into account, the scatter of fatigue test data can also be simulated. Finally, an example is given to show the engineering application of the proposed model. The result shows that the proposed model can correctly reflect the fatigue failure behavior of steel wires of cables in a suspension bridge.
Fatigue crack growth Multi-scale crack model Restraining stress zone Fatigue test data Strain energy density factor Material microstructure Aluminum alloy LY12 Steel wire
Xuesong Tang Xiaobo Zhang
School of Civil Engineering and Architecture, Changsha University of Science and Technology, Changsha, Hunan, 410114, China
国际会议
2011 International Symposium on Structural Integrity 2011国际结构完整性学术研讨会--核工程结构完整性技术 ISSI 2011
合肥
英文
167-173
2011-10-27（万方平台首次上网日期，不代表论文的发表时间）